Category: WoW Tools & Utilities
Addon Information
Works with 3.3
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Author:
Version:
1.18
Date:
01-19-2010 03:24 AM
Size:
5.69 Kb
Downloads:
278,616
Favorites:
569
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Install Script
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Non-Admin or UAC Bypass
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Checker Script
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Batch Mode
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Install Confirmation
Leatrix Latency Fix   Popular! (More than 5000 hits)
An Addon for World of Warcraft by Leatrix
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What does it do?

Leatrix Latency Fix will reduce your World of Warcraft latency significantly by increasing the frequency of TCP acknowledgements sent to the game server. For the technically minded, this is a script which will modify TCPAckFrequency.

You will also see reduced latency in other online games such as Aion, Warhammer and Lord of the Rings. The average reduction in latency (based on feedback from comments) is 66%. Click the Change Log tab above to see a summary of player feedback.

System Requirements

Leatrix Latency Fix is supported on these operating systems only.
  • Windows XP (SP2 or higher)
  • Windows Vista (SP1 or higher)
  • Windows 7
Both 32-bit and 64-bit versions of Windows are supported.
Macintosh users should read the relevant section in the FAQ below.

Installation Instructions

In the download, you'll find 3 script files - Install, Remove and Checker. Simply run the Install script and follow the prompts (as shown here).

If you're logged into your computer with an account which doesn't have Administator privileges (or you're using Windows Vista or Windows 7 with User Account Control enabled), you'll be prompted to enter the credentials of a user account which has Administrator privileges (as shown here).

After the installation, you should see a confirmation window (as shown here). Simply do what it says and restart your computer. If you don't see a confirmation window, or have any other problems with any of the scripts, read the FAQ below.

Once you've restarted your computer, you can login to Wow with reduced latency!

If you want to be sure that Leatrix Latency Fix is installed at any time, run the Checker script and it'll tell you (as shown here). To uninstall Leatrix Latency Fix, run the Remove script.

I recommend that you read this entire page to better understand the process and hopefully any questions you may have will be answered in the FAQ.

How It Works

Wow uses the TCP protocol which requires that network segments sent to your computer be acknowledged in order to provide a reliable connection.

Windows bundles these acknowledgements together and sends them in pairs. While this is an efficient way of dealing with them generally, the inevitable delays caused by the bundling process increase latency considerably.

This is because when Windows queues up an acknowledgement in order to bundle it with the following one, the game server has to wait for the acknowledgement timer to expire before sending new data.

Leatrix Latency Fix removes the acknowledgement bundling process so that an acknowledgement is sent immediately for every segment that's received. This produces a significant reduction in latency as there is no longer a delay before new data is sent to your computer.

In a normal networking environment, you would prioritise network efficiency over latency and use the Windows defaults, but in Wow the opposite is true and you want the lowest latency you can possibly get.

Typical Scenario

If you could listen to a conversation between your computer and the game server, this is what you would hear.

Before Leatrix Latency Fix is installed:
  • Server: "Ok computer, I just sent a data packet over to you, got it?"
  • Your computer: ...
  • Server: "Come on, answer me! I don't have all day!"
  • Your computer: ...
  • Server: "Ok, forget it, I've waited long enough, sending another one over! Got it?"
  • Your computer: "Yep, got that one, also got the one you sent before, thanks."
  • Server: "Well, why didn't you acknowledge the first one when I sent it? I was waiting ages!"
  • Your computer: "Sorry, I'm just trying to make the network more efficient by bundling the acknowledgements together in pairs."
  • Server: "Nevermind efficiency, this isn't a corporate domain you know. You do realise that the longer you take to acknowledge a packet, the more time I have to spend waiting around instead of sending more data?"
  • Your computer: "Well sorry but this is how I'm setup by default."
After Leatrix Latency Fix is installed:
  • Server: "Ok computer, I just sent a data packet over, got it?"
  • Your computer: "Yep, send the next!"
  • Server: "That was fast! Ok, here's another, got that?"
  • Your computer: "Yep, send the next!"
  • Server: "Wow! What an improvement! Now that's more like it! Much better than giving me the silent treatment so I am forced to wait for acknowledgement timeouts, isn't it?
  • Your computer: "Yep, it's certainly keeping me on my toes, thanks!"
Frequently Asked Questions

Got a question? You may find it's already been answered below.

The TcpAckFrequency Change
  • Isn't this the infamous TCP ACK fix?
    Yes, but it's packaged in a neat little script which will make the required changes for you, so you don't need to go messing about with the registry.
  • Doesn't more acknowledgements mean more upload bandwidth used?
    Leatrix Latency Fix doesn't produce more acknowledgements. It produces more frequent acknowledgements.

    Windows, by default, sends two acknowledgements for every two segments received. Leatrix Latency Fix sends one acknowledgement for every segment received. The number of acknowledgements sent in either case is the same, it's only the frequency which is different. The only additional upload bandwidth used is for packet headers.
  • Didn't Blizzard disable this already?
    This is a common misconception but the answer is no. What Blizzard did was disable nagling, way back in patch 2.3.2.

    Nagling bundles small packets together into larger ones for more efficient transmission. The effects are similar - bundling packets together always produces higher latency which is why it's bad for online games. Blizzard disabled nagling because of this, however, the acknowledgement queueing system used by the TCP protocol remains.

    For the technically minded, Blizzard made the TCPNoDelay function redundant, as Wow now includes it by default. They didn't change TcpAckFrequency. Leatrix Latency Fix changes that.
  • The displayed latency is lower but in-game latency is the same isn't it?
    As previously stated, when the game server sends data to your computer, the faster that your computer acknowledges that data, the faster the next lot of data is sent.

    Leatrix Latency Fix makes your computer acknowledge packets immediately, so subsequent data is sent to your computer in the shortest possible time. Anyone who thinks that this doesn't produce a genuine reduction in latency has failed to understand this simple process.

    The in-game latency stat is accurate. However, the amount of latency reduced and how much you notice the benefits depends on your connection and what your character is doing in the game world (since some activities will produce much more traffic than others).
  • Doesn't Wow use UDP for game data?
    No, Wow uses TCP port 3724 for game data and TCP port 1119 for Battle.net authentication. You can prove this to yourself by blocking all outgoing UDP traffic on your computer/router but keeping TCP ports 3724 and 1119 open, the game will still work. But if you block TCP ports 3724 and 1119 then it won't work, it doesn't matter whether UDP ports are open or not.
  • Is Leatrix Latency Fix against the World of Warcraft terms of service?
    Of course not, it's a local change to your computer's network configuration, nothing more. It's completely safe to use and it's nothing to do with Blizzard at all, or any other game publisher.
  • Does Leatrix Latency Fix work with tunneling services?
    Using LLF with a tunneling service probably won't give you any benefit, so you should decide to go with one or the other. There really is no way to find out which works best for you other than trying both yourself. The results really depend on a number of factors which are unique to your connection.

    But be aware. Tunneling services are essentially proxy servers which are rerouting game traffic and your account may be banned if you use these services because Blizzard may interpret your network routing to be suspicious.

    The Terms of Service state that "You agree that you shall not, under any circumstances..redirect the communication protocols used by Blizzard Entertainment in any way.., including.. tunneling.. or any other techniques.. including.. network play utilizing commercial or non-commercial gaming networks. All connections to the Game and/or the Service, whether created by the Game Client or by other tools and utilities, may only be made through methods and means expressly approved by Blizzard Entertainment."

    So use tunneling services at your own risk.

    Leatrix Latency Fix, on the other hand, is a local change to your computer's network configuration and is not against the Terms of Service.
Your Computer
  • Will Leatrix Latency Fix damage my computer? Can I remove it?
    There's a removal script included in the download which will completely erase all traces that Leatrix Latency Fix was ever installed. This isn't one of those scripts that changes all of your network settings and you have to reinstall Windows to get things back to normal. The installation script makes a simple change. The removal script reverses that change. You have nothing to lose.
  • Are there any down sides to running Leatrix Latency Fix?
    Your PC will process acknowledgements faster so it will have to work a bit harder. This may produce a small drop in framerates.

    Remember that Windows networks aren't designed for online games. They're designed for general desktop computing in large networks where traffic efficiency has the highest priority. In these environments, network latency isn't important at all and bundling acknowledgements together makes sense.

    However, Wow players are rather unique in that they'll often use a single TCP based application (the game client) for hours at a time and they'll want to give that application priority over any other function of their PC. It's for these players that Leatrix Latency Fix is designed for.

    Leatrix Latency Fix should not be installed on computers where you want to put more emphasis on network efficiency. Fortunately, this doesn't apply to most Wow players and having reduced latency is of considerably more importance.
  • Does Leatrix Latency Fix work with wireless networks?
    Yes, but for the best latency you should be using a wired connection to your router. Wireless connections have additional overheads and are subject to interference and signal quality. They also can't carry as much data as wired networks which can be a hindrance to the way that Leatrix Latency Fix works. If in doubt, install Leatrix Latency Fix and see for yourself. It won't break anything and there's a removal script included if you need it.
  • Does Leatrix Latency Fix work with routers?
    Of course. The router only forwards packets between your computer and the game server. It doesn't control what packets are forwarded. If your computer acknowledges every single TCP segment or every other TCP segment, it makes no difference, the router will just do what it's told.

    However, routers use a buffering system for forwarding packets and the increased frequency of acknowledgements sent to the game server may cause this buffer to fill up, which will give you lag spikes. This is more likely to happen if you have multiple computers connected to your router, or you're running network intensive applications in the background while playing Wow. There really is no way to find out whether your router will do this other than to try LLF for yourself.
  • Does Leatrix Latency Fix work with any other games?
    Leatrix Latency Fix modifies the way in which Windows handles acknowledgements to TCP segments. As such, it will affect any application that you have installed which uses the TCP protocol to transfer data. A lot of games use UDP so won't be affected but for the games that use TCP (such as World of Warcraft and Aion), you should see a significant reduction in latency.
  • Is there a Macintosh version?
    Leatrix Latency Fix isn't supported on Macs. However, you can achieve lower latency in OSX by entering the following command in a terminal window. This will disable delayed acknowledgements until you restart your computer.

    sudo sysctl -w net.inet.tcp.delayed_ack=0

    To disable them permanently, create a text file under "/etc/" called "sysctl.conf" and copy/paste the following line then restart your computer.

    net.inet.tcp.delayed_ack=0

    To set things back to default, just delete the "sysctl.conf" file and restart your computer.

    If you're not familiar with /etc, it's actually a symbolic link which goes to /private/etc. This is a hidden root folder which isn't normally visible in the Finder.

    To be able to see hidden folders in the Finder, open up a terminal window and type the following:

    defaults write com.apple.finder AppleShowAllFiles TRUE

    Then restart the Finder. To do that, hold down the option key then click and hold on the Finder icon in the dock. When the context menu appears, click Relaunch and the Finder will restart. You should now see all the hidden folders in the Finder, including /etc (either find the Symbolic Link or the actual folder which is inside /private).

    When you're done and you want to hide the hidden folders again, bring up a terminal window and enter the following:

    defaults write com.apple.finder AppleShowAllFiles FALSE

    Then restart the Finder in the same way as before. The hidden folders should now be hidden again.

    Hidden folders contain critical system configuration files so be careful that you don't delete or move anything by mistake while they are visible in the Finder.
The Leatrix Latency Fix Script File
  • I use Windows Vista or Windows 7 and User Account Control prevents me from running scripts. Can I get around it?
    Leatrix Latency Fix includes bypass support for UAC. If you are stuck behind UAC, it will ask you for the credentials of an account which has Administrator rights so that it can run (as shown here).

    Alternatively, you can run Leatrix Latency Fix from an elevated command prompt, which you can access by right-clicking Command Prompt from the start menu while holding down shift and choosing Run As Administrator.
  • Can I install Leatrix Latency Fix without restarting my computer?
    Leatrix Latency Fix will request that you restart your computer after installation. If you really don't want to do this, you can choose not to and instead disable and re-enable your network card.
  • Can I install Leatrix Latency Fix silently from a batch file?
    Yes, just use 'cscript <script name>' in your batch file (eg. 'cscript "c:\Install.vbs"'). Leatrix Latency Fix will detect that you're running it from cscript and output to the command window which launched it instead of a graphical window. The installation script, removal script and checker script all support batch mode, however you need to be logged into your computer with Administrator privileges. Examples of all 3 scripts running in batch mode are shown here.
  • Can I check if Leatrix Latency Fix is installed without running it?
    Simply run the script called "Checker" which is included in the download (as shown here). The Checker script will tell you which interfaces Leatrix Latency Fix is installed on, so that you can be sure it's working.
  • I can't find Leatrix Latency Fix in the Start Menu or Task Manager. Is it installed?
    Leatrix Latency Fix makes a simple change to your network configuration during installation. Nothing is added to the Start Menu and no files are stored on your hard drive. You will see a process in Task Manager called Wscript.exe while any of the scripts are running (installation, removal, checker). Once the script has finished, that process will end. Use the Checker script to find out if Leatrix Latency Fix is installed.
  • Is this spyware, a trojan or any other nasty thing?
    No. I think Wowinterface would have closed my account by now if Leatrix Latency Fix was malicious. The script code can be inspected by anyone to see how it works and exactly what it does.
  • My virus scanner reports that Leatrix Latency Fix is malicious. Is it a false positive?
    Yes, it's a false positive. Leatrix Latency Fix is not malicious. However, certain virus scanners may use their heuristics engine to determine that Leatrix Latency Fix is malicious. To understand why this happens, you need to understand how heuristics works.

    Heuristics scanning involves making an educated guess as to whether a file is malicious or not, based on a number of known legitimate factors. These factors may be deemed by your antivirus program to be included with Leatrix Latency Fix. However, just because a file might possess these factors, that doesn't necessarily mean that it's malicious. The virus scanner simply makes a guess that it is. It's adding 2+2 together and getting 5.

    To my knowledge, Kaspersky Internet Security 2010 is the only virus scanner which reports that Leatrix Latency Fix is malicious. As I said, this is a false positive. It is their heuristics engine which is inaccurate in this case.

    There may be other virus scanners which make use of complicated heuristics to come to the conclusion that Leatrix Latency Fix is malicious (nobody has reported any but since heuristics is not a guaranteed science then it's quite possible). If you are concerned about the safety of using Leatrix Latency Fix, then I suggest that you submit the files to your antivirus developer for analysis. They will confirm that Leatrix Latency Fix is clean, and it may prompt them to do some fine-tuning on their heuristics engine.

    Keep in mind that Wowinterface vets every single upload before making it available to the public, part of this vetting includes a virus scan. Never trust any file downloads from P2P networks or file hosting sites such as Rapidshare. Wowinterface.com is the only official host for Leatrix Latency Fix.
  • Why make a script, why not just make a registry file?
    Because the keys which are modified are unique to the computer you're using, so it's not possible to make a static registry file and expect it to work for everyone.
  • Do I need Administrator rights to run Leatrix Latency Fix?
    Yes, since it modifies keys in HKEY_LOCAL_MACHINE. If you run the script from an account without Administrator rights, you will be prompted for the credentials of a user account which has them (as shown here).
Help! It doesn't work!
  • I installed it and can't see any change in latency. Does it not work on every machine?
    As long as your operating system meets the minimum requirements shown at the top of this page, Leatrix Latency Fix should always work. However, you may have applied a similar fix in the past, either through manual registry changes or from using alternative software. You may not be aware that you have done this. The chances are that if you applied Leatrix Latency Fix on a fresh install of Windows on your computer, it will work, and the reason why it's not working is probably because you've already run some sort of optimisation fix or registry change in the past.
  • I am seeing lower latency values after installing Leatrix Latency Fix, however, I'm now experiencing lag spikes, especially during periods of frantic activity in dungeons. Why is that?
    The increased frequency of acknowledgements has caused your routers buffer to fill up (essentially creating a traffic jam). Very few people have reported this problem so I don't have much information on it. Lag spikes are more likely to occur when you have more than one computer on your network, or if you are running software which produces lots of network activity. If possible, try using a different router with only your computer connected directly to it and don't run network intensive background applications while playing (such as P2P or voice comms).
  • The Checker script says that Leatrix Latency Fix is installed but the IP addresses are listed as 'Unknown'.
    An IP address will be listed as 'Unknown' if Windows doesn't advertise the address to Leatrix Latency Fix. That doesn't mean it's not working. Check that your version of Windows is included in the system requirements at the top of this page, and check your latency figures before and after installation.

    The fact that the checker script lists the interfaces at all means that Leatrix Latency Fix has modified them successfully. It's just that Windows isn't advertising the IP addresses to Leatrix Latency Fix so they're classified as 'Unknown'.
  • I get an error with code 80041002 (or similar). What's that?
    Leatrix Latency Fix requires a functional WMI to work and this error (or similar) suggests that the WMI repository on your computer is corrupt. You may find this site useful to help you fix that. It describes the steps necessary to rebuild a corrupt WMI repository. I advise you to have a backup in place first. Note that this is a problem with your computer, not with Leatrix Latency Fix.
  • I get an error "Can't find script engine VBScript" and some more text. What's that?
    For some reason, the VBScript engine has been removed from your system. Click Start, click Run and enter "regsvr32 VBScript" (without quotes). You should receive a message that it succeeded. If so, try Leatrix Latency Fix again.

    If you're using a 64-bit version of Windows, you may need to register vbscript.dll in the SysWOW64 folder. To do that, bring up a command prompt, type in "CD C:\Windows\SysWOW64" and then type in "regsvr32 VBScript.dll".
  • I get an error to do with NTVDM. What's that?
    NTVDM is the Microsoft Virtual DOS Machine and an error associated with this usually means that Windows is trying to run the script with an invalid shell. This could be because system files have been replaced on your machine (possibly the result of a virus attack). You should consider running a Windows repair or reinstalling Windows completely.
  • I get an error, it just says error 1. What's that?
    Error 1 is a generic runtime error. It's not possible to isolate the cause of this error, but it's probably related to the security configuration of your computer. This could be to do with antivirus software, group policy (if it's a domain controlled computer) or something along those lines. Basically, your computer isn't letting LLF do its job.
  • When I double-click the script file, it opens in another application (such as Notepad) instead of running it. Why is that?
    For some reason, VBScript files are associated with another application on your computer. This is probably the result of some software you installed in the past or some registry change that you made.

    VBScript files should instead be associated with the VBScript engine so that they can run. This is the default behaviour in Windows.

    To rectify this, do the following.

    Right-click the script file and choose "Open With...". A window will appear listing a selection of programs that you can open VBScript files with. If "Microsoft Windows Based Script Host" (or similar) is shown in the list, choose that, then check the "Always use the selected program" button and click Ok.

    If "Microsoft Windows Based Script Host" (or similar) isn't shown in the list, click Browse. Navigate to your System32 folder (normally "C:\Windows\System32") and choose Wscript. Again, check the "Always use the selected program" button and click Ok.

    VBScript files will now open with the VBScript engine and they'll run fine.
  • I ran Leatrix Latency Fix and it didn't show a confirmation window. Did it work?
    No. If Leatrix Latency Fix installs successfully, it will always show a confirmation window and ask you to restart your computer (as shown here). If you don't see a confirmation window, then it hasn't installed successfully.

    The most likely reason for a confirmation window not showing is that you've encountered the User Account Control window (as shown here) but you haven't provided the credentials of an account which has Admnistrator rights.

    You should check the radio button for "The following user" and enter the username in the format of "computername\username". For example, if the computer name is AND and the username is Administrator, you should enter AND\Administrator (as shown here). The username which you enter must have Administrator rights on the computer.
  • Even after installing Leatrix Latency Fix, my latency is still terrible, how can I find out where the problem lies?
    You need to understand that Leatrix Latency Fix will make a good connection faster and more responsive. It won't magically fix a bad connection. You can get an indication whether your connection is good or bad using the PATHPING command which is included in Windows.

    First, uninstall Leatrix Latency Fix just to ensure that it doesn't interfere with the results.

    Now, you need to find out the IP address of the game server you're connected to. To do that, launch Wow, and ensure your realm is chosen and your character list is shown (you don't need to login to the game world with your character). Now bring up a command prompt (press CTRL and ESCAPE together if you can't see your desktop to do that).

    In the command prompt window, type in NETSTAT. You will see a list of active connections. One of the entries will have :3724 after it. This means port 3724 which is the port that Wow uses. This is the entry that you want. If you have more than one entry with :3724 after it, choose the one which says ESTABLISHED.

    To the left of :3724, you will see the address of the game server that your computer is connected to. For example, on my computer, one of the entries reads "213-248-123-43.customer.teliacarrier.com:3724 ESTABLISHED", so the address of the game server is "213-248-123-43.customer.teliacarrier.com".

    Now, type in "PATHPING <address>" where <address> is the address of the game server as explained above. In my example, I would type in "PATHPING 213-248-123-43.customer.teliacarrier.com".

    If you've done it right, you will see a route being traced from your computer to the game server. Packets travelling along this route hop from one router to another on their way to the game server destination and each line in the results represents one hop.

    Some of these hops will return * as the result, which means that the hop being polled didn't respond. That's fine as long as all the lines with * are grouped together at the bottom of the list, because the hops at the bottom of the list belong to Blizzard. Blizzard's network is protected so Pathping won't be able to detect that there's anything there.

    Now, you'll see a message saying "Computing statistics for...". Just leave it running there for a few minutes, after which it will output the final results.

    The first line or two in the results will show the address of your computer and gateway or router. The next few lines will be your ISP and you'll probably see references to it (or the carrier they are using) in the address field for each line. Then you'll see lines with "telia.net" in the address field. These hops are at Blizzards end.

    Each line of the results will contain something like this:

    7 56ms 0/ 100 = 0% 0/ 100 = 0% hbg-bb1-link.telia.net [80.239.147.182]

    In the example above, 7 is the hop number and 56ms is the ping for that hop. If you see a high ping for a particular hop which is not consistent with other hop pings, there could be a problem with that hop.

    The "0/ 100 = 0%" field shows how many packets were lost on that hop. It should show 0/ 100 to indicate 0 packets lost, but if there's a problem with that hop, you will see a higher number. For example, if there were 23 packets lost out of 100, you would see "23/100 = 23%".

    The address for that hop is shown at the end of the line (in the example above, the address is hbg-bb1-link.telia.net) along with the IP address.

    By looking which hop has a high ping time or shows a number of packets lost, and seeing which address that hop is for, you can get an indication whether the problem is with your ISPs routing or Blizzards routing.

    Your ISP will be able to conduct line tests and possibly suggest optimising your line for low latency (more on this further down in the FAQ). Sometimes, however, there's simply nothing that can be done due to the quality of your line or the distance from your local exchange, or perhaps the ISP (or carrier) is simply overloaded.

    Blizzard tend to look at latency issues only when they are widespread and affecting a lot of users (which doesn't happen very often). If you do submit a ticket to them for help with your latency, it will help your case greatly to include a PATHPING report. Note, however, that Blizzard won't do anything if they notice that your report shows higher latency or dropped packets on hops prior to reaching their network (telia.net). They will simply advise you to contact your ISP.

    To help you submit a Pathping report, you can output the results to a text file using the pipe switch. Using my original example, this is what I would type to pipe the results to a text file called results.txt.

    PATHPING 213-248-123-43.customer.teliacarrier.com > results.txt

    Entering this will not output anything to the screen, but when the command prompt has returned to you, there will be a file called results.txt which will contain the output of the PATHPING command, allowing you to copy/paste the text into a web form or email.
  • I think the problem is with my internet provider. Can they change anything from their end?
    You can contact your ISP and ask them to optimise your broadband line for low latency. The terminolgy used to describe a low latency optimisation differs depending on your location and broadband type. In the UK, it can be known as Fastpath or Max Delay Reduction. If in doubt what to ask for, speak to your ISP and tell them you have high latency in World of Warcraft.

    Optimising your line will lower your overall bandwidth slightly. In rare cases, it can make your line unstable if the quality of your line isn't very good to begin with. However, most people report a much improved experience with faster ping times and quicker in-game responses.
  • Is my latency affected by my choice of internet provider?
    Your choice of internet provider can have a big effect on your in-game latency. Most internet providers use traffic shaping to manage bandwidth efficiently, but this usually has a side effect of increasing your latency.

    Some providers use traffic shaping to prioritise gaming packets, resulting in lower latency when playing online games. On the other hand, some providers don't use traffic shaping at all, which is great as long as they maintain enough capacity to sustain that.

    Traffic shaping is like traffic congestion control on the roads. It slows everyone down a bit, but if the roads are busy then it helps things run smoothly. However, if the roads aren't so busy, congestion control will simply slow down your speed needlessly.

    You should do your research before choosing a provider to find out what they do for gamers. Traffic shaping is fine as long as the shaper detects and prioritises gaming packets. Unshaped traffic will produce the best results if the network has enough capacity, otherwise it will be worse than shaping. Finally, avoid internet providers that use traffic shaping but don't prioritise gaming packets.
  • I have an issue with Leatrix Latency Fix that is not mentioned above. Can you fix it?
    Reports of Leatrix Latency Fix producing an error or not working are very rare. However, if you experience an issue, I'll do my best to fix it. Please describe your issue in the comments section, giving me as much detail as possible. Don't just tell me that it doesn't work. The information that you give me is part of the solution.

    Include your operating system, service pack and exact error wording. Also explain what you have tried to do (i.e. install using Administrator account, install using batch mode, etc).

    Of the few problems that have been reported with LLF, it usually turns out to be a fault with the users own computer and a fresh install of Windows on the same computer does not reproduce the problem. Please keep this in mind.
And finally...!

Stop worrying and wondering whether Leatrix Latency Fix is right for you. It makes a simple change to your computer, there's a removal script in the download which removes that change.

Install it, try it for yourself over a period of a few days. If you aren't happy, remove it. Make up your own mind. It won't break anything. Most people report a noticeable improvement in button response times, as well as smoother mob movement patterns. You'll probably be one of them. So relax and stop worrying, try it and see for yourself.

A Note from the Author

Leatrix Latency Fix is a script which will modify the TCP acknowledgement process, effectively lowering your latency in online games by speeding up the transmission of data being sent from server to client. It will make a good connection faster and more responsive.

I have written an installation script, removal script and checking script, and I've compiled a huge FAQ which covers almost every possible problem, and I've published the whole lot on Wowinterface for free. I've also been here to respond to comments on a wide range of issues and I've done all that for the Wow community.

If you're new to Leatrix Latency Fix and have a problem installing it, read the FAQ.

If you have a problem while Leatrix Latency Fix is installed, remove every possible cause from your network (ensure you're the only one connected to your gateway, disable all addons, remove any software which produces lots of network activity such as Teamspeak). If you still have problems, report them in the comments. I shall investigate them if I feel they are worth my time to do so.

Keep in mind that 99% of problems reported with Leatrix Latency Fix have been caused by issues with the users own computer or network, and after my own investigations, this has proven to be the case time after time after time. I've included the most common user problems in the FAQ.

There's also a removal script included in the download which will remove all traces of Leatrix Latency Fix on every network interface. Some people assume that Leatrix Latency Fix leaves behind fragments of data after it's been removed. It doesn't. Running the remove script and restarting your computer is all you need to do to completely remove Leatrix Latency Fix. If you have any problems after that, they are not caused by Leatrix Latency Fix. If the Checker script reports that Leatrix Latency Fix is not installed on any network interfaces, then it simply doesn't exist.

I won't be providing much feedback in the Comments section in future. I think that Leatrix Latency Fix has reached a point where almost all possible problems have been covered in the FAQ and recent discussions in the comments have not been helpful, either to the Wow community or the future of Leatrix Latency Fix.

I shall release updates to Leatrix Latency Fix if they are needed and this is the website where they will be published. I've noticed that Leatrix Latency Fix has been available on Torrent sites for some time now, as well as various "warez" sites. Do not trust any scripts which are available on such sites and, even better, don't use P2P at all.

Wowinterface.com is the only home for Leatrix Latency Fix and that's the only site where you should download it from. A link to Leatrix Latency Fix on Wowinterface is included in the download, as well as on my own website of Leatrix.com.

Links

Here's some randomly selected websites with references to Leatrix Latency Fix. Keep in mind that these are just user opinions, not all forum posts are accurate.

VideosBlogsNews SitesForumsGuildsLeatrix Addons
  • For more addons by Leatrix, click here or here.
  Change Log - Leatrix Latency Fix
Change Log:
  • 1.18 - The Checker script will now show which network interfaces Leatrix Latency Fix is installed on.
  • 1.15 - Added support for batch mode. You can now run Leatrix Latency Fix from your own batch files. Just use 'cscript <script name.vbs>' in your batch file (eg. 'cscript c:\install.vbs'). Batch mode allows you to integrate Leatrix Latency Fix into logon scripts and automated Windows setup scripts. You must be logged into your computer with an Administrator account to use batch mode.
  • 1.12 - Added a checker script which will simply inform you whether Leatrix Latency Fix is installed or not.
  • 1.11 - Added support for User Account Control.
  • 1.00 - First release.

Code:

 This is a summary of reported Wow latency values taken from player comments.
 The overall average reduction is around 66%.
 
 Name          Before    After     Saving   Operating System
 Ckramme       280-330   44-87     89%      Windows 7 Beta
 Epitome       300-400   30-65     87%      Windows XP SP3
 Halstrom      105-155   16-21     85%
 Silenia       96-123    16        85%      Windows Vista 64bit SP1
 Skylinee      250       40        84%      Windows Vista 64bit
 Mozzi         200-300   60-80     84%      Windows 7 Beta
 Katira        586       107       82%
 Namtar        150-250   35-40     80%      Windows XP SP3
 Des1963       150-190   32-40     79%
 Shadout       100-250   30        79%      Windows Vista 64bit SP1
 Bulbul        80-100    20        77%      Windows XP SP3
 Haylie        150-200   30-50     77%      Windows Vista SP1
 Leatrix       200       55        73%      Windows XP SP3
 Marthisdil    220       70        68%
 Kunstbanause  170       55        67%      Windows Vista 64bit
 Makronom      180-200   60-70     66%
 Breener       160-250   67        66%      Windows Vista 64bit SP1
 Aceman67      356       124       65%      Windows 7 Beta
 Chobaka       100-200   40-60     65%      Windows XP SP3
 Khuul         150-250   70        63%      Windows XP SP3
 Kristie       250       100       60%      Windows 7 Beta
 Phrozenassid  180-280   90-120    54%
 XMushroom     170       80        53%      Windows Vista SP1
 Smikules      230       115       50%      Windows 7 Beta
 Toadstool     400-500   250       44%      Windows Vista SP1
 Mooshroom     300-400   200       41%
 Bleukreuz     350-450   250       36%      Windows Vista SP1
 Servi         150-300   100-200   33%      Windows XP SP3
 Alsenfaire    500-800   400-500   29%      Windows XP SP3
 
  Archived Versions - Leatrix Latency Fix
File Name
Version
Size
Author
Date
1.15
6kB
Leatrix
09-23-2009 12:01 AM
1.12
5kB
Leatrix
09-08-2009 04:18 AM
  Comments - Leatrix Latency Fix
Post A Reply Comment Options
Old Today, 09:40 AM  
Leatrix
A Kobold Labourer
Interface Author - Click to view interfaces

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File comments: 134
Uploads: 8
Re: BT

Quote:
Originally posted by wclord
hi

if i am using bitcomet to download stuff

will this affect the speed of bt at all?

thanks
Try it and see. You may find that Leatrix Latency Fix will reduce your overall P2P bandwidth a bit, as it's a latency fix for games, not a bandwidth or P2P fix for file sharers.

You can always remove Leatrix Latency Fix whenever you want to use P2P. You don't need to restart your computer when prompted, if you know how to disable and enable your network card. But try it with P2P running and see what you think, it won't break anything.

You should never run P2P while playing Wow unless you can control the upload bandwidth used, and even then it'll use a ton of resources, increase latency and slow down your game. I've read lots of reports of latency problems in Wow, with people not realising that their P2P application is running in the background.

It's worth noting that your ISP may also limit your connection if you use P2P by lowering the priority of all your data packets, which will in turn affect your Wow latency. Some ISPs do this, as it's well known that P2P file sharing accounts for lots of network capacity problems which actually makes the network worse for everyone. As a result, if your ISP detects that you are using P2P frequently, they may switch all of your data packets to low priority, and usually they don't have to tell you that they have done this, and may even deny it if you ask. Just something to keep in mind.

Last edited by Leatrix : 02-09-2010 at 09:42 AM.
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Old Today, 03:32 AM  
wclord
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BT

hi

if i am using bitcomet to download stuff

will this affect the speed of bt at all?

thanks
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Old 02-07-2010, 08:20 AM  
Leatrix
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Quote:
Originally posted by EnderXi
Kaspersky, joyus thing it is now wont even let you download it says the following:

Im guessing this is yet another false positive but not sure, anyone else had this?
Yes, it's a false positive. The clue is in the error. Kaspersky is using it's heuristics engine to make a guess that the file is malicious. That guess is wrong and Kaspersky's heuristics engine is inaccurate. You should email the file to Kaspersky and tell them to update their heuristics engine.

Kaspersky also allows you to submit suspected virus threats for analysis. Use that feature to send Leatrix Latency Fix to them, and then come back here and post your reply. You'll find that they admit it's a false positive (though they probably won't admit their heuristics engine needs more fine tuning, but evidently it does).

A threat reported from a heuristics scan is not necessarily a real threat, it's only a guess. A real threat would come from a virus signature which has been found in the file. Leatrix Latency Fix does not have any virus signatures, obviously. Kaspersky is guessing it's a virus purely from inaccurate heuristics scanning.

You can tell this from two things. For one, the keyword HEUR is in the error that's shown. When you see that, it means that Kaspersky is guessing what the file is as it doesn't actually know itself what the file is. It's using heuristics. Heuristics does not mean evidence, it merely means a conclusion reached from legitimate factors. That conclusion is not always right. That's how you get false positives.

For two, only Kaspersky is reporting it as a virus. None of the other virus scanners are. That's because Kaspersky's heuristics engine is inaccurate.

Now, there may be other virus scanners which make use of complicated heuristics to come to the conclusion that Leatrix Latency Fix is malicious (nobody has reported any but since heuristics is not a guaranteed science then it's quite possible). It depends on how accurate their heuristics engine is. I've had Avast Professional installed in the past and that reported my domain logon script to be malicious, yet obviously it isn't. Avast was using it's heuristics engine to make a guess due to the fact that my domain logon script modifies some system parameters.

From the FAQ:
Quote:
My virus scanner reports that Leatrix Latency Fix is malicious. Is it a false positive?
Yes, it's a false positive. Leatrix Latency Fix is not malicious. However, certain virus scanners may use their heuristics engine to determine that Leatrix Latency Fix is malicious. To understand why that happens, you need to understand how heuristics works.

Heuristics scanning involves making an educated guess as to whether a file is malicious or not, based on a number of known legitimate factors. Those factors may be deemed by your antivirus program to be included with Leatrix Latency Fix. However, just because a file might possess those factors, that doesn't necessarily mean that it's malicious. The virus scanner simply makes a guess that it is.

To my knowledge, Kaspersky Internet Security 2010 is the only virus scanner which reports that Leatrix Latency Fix is malicious. As I said, this is a false positive. It is their heuristics engine which is inaccurate. It's added 2+2 together and got 5.

Also keep in mind that Wowinterface vets every single upload before making it available to the public, part of this vetting includes a virus scan. Never trust any file downloads from P2P networks or file hosting sites such as Rapidshare. Wowinterface.com is the only official host for Leatrix Latency Fix.
Wowinterface.com would not allow Leatrix Latency Fix to be hosted here if it was malicious, they're very thorough on vetting every upload manually before allowing it to be made public. On this issue, there's no need to report any more heuristics scans from Kaspersky, thank you for your feedback. Kaspersky's heuristics engine is inaccurate, a heuristics threat is not a real threat, it's only a guess. In Kaspersky's case, that guess is wrong. That's all there is to be said.
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Old 02-07-2010, 06:10 AM  
EnderXi
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Kaspersky, joyus thing it is now wont even let you download it says the following:

The requested URL could not be retrieved

While trying to retrieve the URL:

http://fs.wowinterface.com/download.php?
id=13581

The following threat was encountered:

The requested object is INFECTED with the following viruses: HEUR:Trojan-Dropper.Script.Generic
Generated:
11:05:34
Kaspersky Internet Security 2010

Just a blanket block, no way round it doesnt give you any options, they only thing to do is turn it off download and then on again.

Im guessing this is yet another false positive but not sure, anyone else had this?
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Old 02-06-2010, 07:00 AM  
Leatrix
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Interface Author - Click to view interfaces

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File comments: 134
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Re: Detected as Trojan

Quote:
Originally posted by scaife
Leatrix is detected as containing HEUR:Trojan-Dropper.Script.Generic by Kaspersky Internet Security 2010.

--> http://imgur.com/yGtc9.jpg

Code:
06/02/2010 10:18:36	Infecté	virus HEUR:Trojan-Dropper.Script.Generic	http://fs.wowinterface.com/download.php?id=13581/Leatrix Latency Fix 1.18/Install.vbs
False positive ?
Yes, it's a false positive. Kaspersky Internet Security 2010 didn't find any virus signatures in Leatrix Latency Fix, so it's using it's heuristics engine to make an educated guess as to whether Leatrix Latency Fix is malicious. In this case, Kaspersky's heuristics engine is incorrect and has indeed shown a false positive.

This link shows a test done with 40 virus scanners, none of which report that Leatrix Latency Fix is a virus. If you want to do the test yourself, make sure you select to reanalyse the file after uploading it. Don't just preview a cached test result, because some people have been uploading scripts from P2P networks.

If in doubt, email the file to Kasperksy, or ask Wowinterface.com to investigate (you do realise that Wowinterface vets every single upload before allowing it to be made available), or test it with other virus scanners. Also ensure that you only ever download the script file from this website, never trust P2P networks or file sharing hosts such as Rapidshare.

I've added this question to the FAQ. Thanks for your feedback.

Last edited by Leatrix : 02-06-2010 at 07:29 AM.
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Old 02-06-2010, 06:45 AM  
glamrockcop
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Re: Detected as Trojan

Just had the same thing happen with KIS 2010.



Quote:
Originally posted by scaife
Leatrix is detected as containing HEUR:Trojan-Dropper.Script.Generic by Kaspersky Internet Security 2010.

--> http://imgur.com/yGtc9.jpg

Code:
06/02/2010 10:18:36	Infecté	virus HEUR:Trojan-Dropper.Script.Generic	http://fs.wowinterface.com/download.php?id=13581/Leatrix Latency Fix 1.18/Install.vbs
False positive ?
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Old 02-06-2010, 04:24 AM  
scaife
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File comments: 14
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Detected as Trojan

Leatrix is detected as containing HEUR:Trojan-Dropper.Script.Generic by Kaspersky Internet Security 2010.

--> http://imgur.com/yGtc9.jpg

Code:
06/02/2010 10:18:36	Infecté	virus HEUR:Trojan-Dropper.Script.Generic	http://fs.wowinterface.com/download.php?id=13581/Leatrix Latency Fix 1.18/Install.vbs
False positive ?

Last edited by scaife : 02-06-2010 at 04:28 AM.
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Old 02-05-2010, 02:21 PM  
mactag
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OMG! i chuffing LOVE YOU! ive been having so many probs with latency in wow & now your script has cut my latency down to a 1/4!


Last edited by mactag : 02-05-2010 at 02:22 PM.
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Old 02-03-2010, 04:51 PM  
kaikkis
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does this rly work?

Hello
i installed the fix as it was.
Yes my latency went down as others have stated.
Altho i saw no change in game and ppl telling there is high latency like in some bg's or raids.. well to me it was always under 100 ms. BUT the game was still laggy as hell.. framerate was high as always since got pretty new machine. but the thing is i don't rly believe this is doing all that much tbh. It looks good in numbers at latency meter, but when you play the game and get into the situations where the lag is usually there.. it still is.. with or without this fix.. only problem is that with the fix you cannot see the real numbers...
prove me wrong..
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Old 02-03-2010, 02:34 PM  
Popa_popa
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Problem with install on Vista. help pleaze!

I have such error when installing it:

Can't find execute core vbscript: and here way to file...

Help...
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Old 02-01-2010, 04:11 PM  
LDB10671
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Im on an expensive high end i7 system.

My pings went from ~150 down to less than 50.

It works great.
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Old 01-29-2010, 02:34 PM  
HarlequinNikki
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Using Windows Vista and a considerably nice graphics card with stable, fast internet connection, I experienced an issue with latency starting about a week ago; though my other online programs responded fine as usual, WoW was between 900-2000 latency at all times.

After installing Latency Fix and rebooting, WoW ran at about 100-300 latency again, consistently, no matter where in Azeroth I was or what I was doing.

Until the next day.

Now I am experiencing the same problem again, as if I'd never downloaded Latency Fix. The Checker tells me it is still installed and working.

Any ideas of why? Or how to fix this problem?
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Old 01-26-2010, 01:09 PM  
Jegar48
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Re: Latenfy Fix Results

Before: Anywhere from 275 to 375 MS depending on what dungeon, raid or zone I was in.

After: Consistently 124 MS no matter where I am.

This with no significant drop in frame rate.

Windows XP SP3
Intel Core2 Duo CPU EZ7400@ 2.8 GHZ, 3.2 GB RAM, Nvidia GeForce 9500 GT (512 MB RAM)

BTW, there is a note that this fix works better if you are hooked directly to your router, however I have seen the above results even though I am using a wireless hook up in a different room across the house from where the router is.

If your web page hit number has gone up in the past few days it's my fault, I've been telling everyone I know in the game about this great little utility.

Last edited by Jegar48 : 01-26-2010 at 01:23 PM.
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Old 01-24-2010, 01:22 AM  
Leatrix
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Interface Author - Click to view interfaces

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File comments: 134
Uploads: 8
Re: Task manager

Quote:
Originally posted by Qwet
I have seen a small reduction in my latency of about 50ms, but I do not see anything named "wscript.exe" when I open task manager... does this mean it is not working properly?
Question added to FAQ, "I can't find Leatrix Latency Fix in the Start Menu or Task Manager. Is it installed?"
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Old 01-23-2010, 11:53 PM  
Qwet
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Task manager

I have seen a small reduction in my latency of about 50ms, but I do not see anything named "wscript.exe" when I open task manager... does this mean it is not working properly?
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