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[Tutorial] GMod CEF Codec Fix - Windows

Discussion in 'Help and Support' started by Sophie-bear, Jun 21, 2019.

  1. Sophie-bear

    Sophie-bear 3D Modeler Staff Member Developer

    Dec 29, 2015
    Likes Received:
    Step-by-step Guide to setting up GMod CEF Codec Fix on Windows
    Note: Garry's Mod must be closed before following this guide.
    If you are already on the [x86-64] branch, skip to step 5!
    Other tutorials: Linux | macOS

    1. Open Steam, then right click Garry's Mod from your Library games list. Select Properties from the menu.


    2. In the properties window, switch to the "Betas" tab.


    3. From the Betas tab, click on the Dropdown menu and select "x86-64 - Chromium + 64-bit Binaries"


    4. Now you can close the properties window and wait for the update to download. Proceed to step 5 in the Operating System spoilers below.

    5. When the update is finished downloading, go to Releases on the GMod CEF Codec Fix Github page.

    6. From that page, under Assets, click the appropriate package for your operating system to download the script. Use the version closest to the top of the page, that's the newest one!


    7. Run the executable file you just downloaded. Allow the app through your Windows SmartScreen filter if necessary.



    8. When the script runs, it will say what it is doing. If the files are not patched yet, the patches will download. Depending on your internet speed, this step can take a moment.

    9. When finished launch GMod (64-bit version) from the GModCEFCodecFix window by typing the corresponding number and pressing Enter. Only launch the 32-bit version if you have a 32-bit processor.


    Congratulations! If you made it this far, you're done. Luckily the script does pretty much all of the work for us this time.

    To avoid the file patches reverting to the files included with GMod, be sure to use the GModCEFCodecFix script to launch GMod, or launch GMod via your games list or .exe shortcut only. Using most methods of game launching on Steam forces a file validation pass which will revert these patches. You'll have to run the script again to re-patch the files if you do this.


    Optional Enhancement: Auto-mode
    This enables you to use the GModCEFCodecFix as a launcher without having to input a number to launch GMod when it finishes.

    1. Right click on the GModCEFCodecFix.exe you previously downloaded and Create a Shortcut. This Shortcut can be put anywhere on your PC.

    2. Right click on your new Shortcut and go to Properties.

    3. From the Shortcut tab in the Properties window, find the Target text field. At the end of the text field, after GModCEFCodecFix.exe, add a space, then the text "-a 2". After you apply this change, using this shortcut will automatically launch 64-bit GMod. (Use "-a 1" if you need to launch 32-bit GMod instead.)
    Last edited by a moderator: Mar 28, 2020
    Beako, pantera and Mottinator100 like this.