Change UI language without changing Steam default language

This guide is a workaround to allow you to play Black Mesa in your desired in-game language without having to change Steam client app default language.

Introduction

Black Mesa and most of Source games doesn’t let you change the UI language from in-game options nor from Steam game properties. Instead, they assume *wrong* that all people would like to play it with their Steam client app default language. Hopefully there is a workaround.

Note

The easy way is to just change the language of your Steam client app and restart. Then Black Mesa will be in that language if supported next time you launch it. Follow the official Steam FAQ steps . Continue reading if you really want to change the game language but keep your current steam app language.

Force specific language for Source games without changing Steam language

This is a bit tricky. As always be careful when editing Windows Registry values.

1. Launch the game and minimize it
   
2. Open Registry editor: Win+R and type regedit
   
3. Goto

    HKEY_CURRENT_USER\Software\Valve\Source

4. Change the value of the key Language to english or another language
   
5. Under Source there will be bms and Settings folder. Right-click on each of them: Permissions – Advanced – Disable inheritance – Convert permissions – Ok to close dialog.
   
6. Right-click on Source folder – Permissions, then change all groups and users to Denied Total control and press ok and then ok on the warning.
   
7. Restart the game and the UI should be in that language.

Final notes

Probably this change is affecting other Source games, not just Black Mesa, but have not tried it. Please leave a comment if this worked for you on other games or if having any issues.

This is a common problem on Source games since the HL2 days where you can cannot choose freely the language of the UI. Please devs, take account internationalization and allow players to choose their desired language in-game.

Originally posted by lds1998:

Based on their guide but added extra steps fixing recent launch error