Unreal Tournament 2004 fullscreen not working [Windows 10/11]

Ivan Jenic
by Ivan Jenic
Troubleshooting Expert
Passionate about all elements related to Windows and combined with his innate curiosity, Ivan has delved deep into understanding this operating system, with a specialization in drivers and driver troubleshooting. When he's not tackling... Read more
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Solve Unreal Tournament 2004 Isn't Working in Fullscreen on Windows 10 errors

Windows 10 is the latest operating system from Microsoft, and sometimes new operating systems have issues with older software. One of these issues is related to a video game called Unreal Tournament 2004.

Users report that Unreal Tournament 2004 isn’t working in fullscreen, so let’s see if we can fix this.

Unreal Tournament 2004 is an old game, so some issues are expected. Users report that they are getting errors when they are trying to run the game in fullscreen.

This isn’t just related to Unreal Tournament 2004 and other games that use Unreal 2 engine are having these issues as well.

It appears that there are no issues in window mode, but let’s see if we can make Unreal Tournament 2004 run in fullscreen.

What to do if Unreal Tournament 2004 isn’t working in fullscreen:

  1. Use OpenGL
  2. Set ReduceMouseLag to False
  3. Run the 64-bit version of the game

Solution 1 – Use OpenGL

To do this, you’ll need to locate the UT2004.ini file and change it. This file should be located in the Unreal Tournament 2004 installation directory.

When you find the installation directory, locate the System folder and in there you should find UT2004.ini.

  1. Right click UT2004.ini and choose Open With.
  2. Select Notepad from the list of applications.
  3. Find the following lines and set them to these values:
    • [Engine.Engine]
    • ;RenderDevice=D3D9Drv.D3D9RenderDevice
    • RenderDevice=OpenGLDrv.OpenGLRenderDevice
  4. Save the changes.

Now your game should be working properly.

Solution 2 – Set ReduceMouseLag to False

  1. Open the UT2004.ini file like in previous solution.
  2. Find the ReduceMouseLag=False and set it to ReduceMouseLag=True.
  3. Save the changes and start the game.

Solution 3 – Run the 64-bit version of the game

These issues with fullscreen appear only on 32-bit version of Unreal Tournament 2004, so you might want to try using the 64-bit version of the game. If you have all the patches, you probably have 64-bit version launcher for the game in its installation directory.

We hope that one of our solutions worked for you. Feel free to tell us in the comments section below what other issues did you encountered in UT2k4 and how did you fixed them.

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