Reset the Source SDK Game Configuration
From Valve Developer Community
If you're experiencing problems with the Hammer game configuration or SDK Launcher game configuration not behaving correctly, you can follow this procedure to reset the game configurations to the default state.
If you have not created a custom Mod through the "Create A Mod" wizard:
- Shut down any Source SDK Tools, such as Hammer or FacePoser.
- Open the Source SDK application from the Steam Window, under the Tools section.
- Choose Reset Game Configurations from the Source SDK window.
- Click Reset to reset your game configurations to the defaults.
If you have created a Mod through the "Create A Mod" wizard, see the following page on Resetting a Custom Mod Game Configuration.
Still having problems?
If after resetting the Game Configuration the tools still do not run correctly, this usually means that the SDK tools cannot find the
Gameinfo.txt for the game or mod you want to work with. To fix this error with a Valve Software game (e.g. Half-Life 2, Counter-Strike: Source, etc.), simply run the game then restart the Source SDK. If it is a third-party or custom modification, you will need to manually create a configuration specific to that Mod. Read The GameInfo.txt File Structure and Hammer Manual Configuration for more information.
If you are still having issues then you might want to get additional help.