Mass Effect

Mass Effect Mouse Fix

What is this?

This fix makes Mass Effect use raw mouse input and removes the game’s mouse acceleration. It is easy to install and use and does not require any external configuration.



While the mouse controls are pretty responsive, the first Mass Effect suffers from mouse acceleration, which can’t be turned off via the ingame settings or with the usual approaches for other Unreal Engine 3 games.

This fix removes the acceleration by acquiring raw mouse input and injecting it directly into the game’s input function.

Important: This is an experimental fix. Although I tested all supported versions for some time, I played none of them all the way through. There might be crashes or other issues that I’m not aware of that may require further updates.


  • Raw mouse input
  • No additional smoothing or positive/negative mouse acceleration
  • Configuration via the ingame settings as usual
  • Simple installation and usage without any external configuration


Supported Versions

Important: This fix relies on the latest, fully patched executables of the supported versions. Older versions or ones that otherwise have been tempered with won’t work. This also means that if a game were to be patched — which is very unlikely at this point — it would break the fix and require it to be updated.

  • Steam
  • Origin
  • Retail, v1.02

Note: All available versions of the game can be enabled on Origin one way or another. See this link for details.


Note: The fix does not make any permanent changes to the game or the system and can easily be removed (see below).

  1. Extract the file dinput8.dll to your main game folder. For example: "C:\Program Files (x86)\Steam\steamapps\common\Mass Effect\Binaries\"
  2. (Optional) If you want to use the fix with other fixes/mods that also use a dinput8.dll, rename the file to xinput1_3.dll
  3. Start the game like you would normally, for example directly through Steam or Origin


  1. Remove or rename the dinput8.dll from the folder of the game.

How To Use

After the installation the fix does not require any additional treatment. Just launch and configure the game as usual.

Upon start the fix will detect which version you are using and immediately alert you via a dialog box and terminate the process if something goes wrong. This is to ensure that users don’t assume the fix is loaded when they are actually using an unsupported version.

Additional Information

What You Should Know

This fix is essentially a hack and relies on the layout of the specific executable. There may be crashes or unexpected issues. Feel free to provide feedback so that the problems can get fixed.

Since the fix consists of an executable DLL-File, I could have put any harmful shenanigans in there. You just have to trust me that the file is clean.

If you don’t — and why should you — feel free to use a meta online virus scanner like VirusTotal to verify the file. Be aware however, that because the fix uses “hacking techniques” such as injection and hooking, it could trigger anti-virus software without being harmful.

Known Issues

There are currently no known issues with using the fix.

Contact And Support

If you like this mod and want to support the development or show your appreciation, you can find more information on my website. There you can also find out more about other fixes that I have done and means to contact me if you have a question, want to provide feedback, bug reports or suggestions.

Version History

Beta 0.6:

  • The camera will no longer move when the player is in a menu
  • The fix will now respect the inversion setting of the y-axis

Beta 0.5.1 – Hotfix:

  • Fixed bug that caused the Steam and retail version to crash on start

Beta 0.5:

  • The fix should now correctly work with Origin versions from any region

Beta 0.4:

  • The DLL can now also be renamed and used as xinput1_3.dll. This is to make the fix compatible with other fixes/mods that also use a dinput8.dll for loading

Beta 0.3:

  • Patching a supported version to be large address aware no longer prevents it from being detected correctly. This is to ensure that the fix works with certain mods

Beta 0.2:

  • Added support for retail version of the game

Beta 0.1:

  • Initial release