Go to C:\Program Files (x86)\Steam\steamapps\common\left 4 dead 2
or some other game you have installed.
If there is a steam_appid.txt, open it and change the number to 620.
If not, create a steam_appid.txt
The steam id of Portal 2 is 620.
Save the file in that folder, and run the game from the folder.
Launching the game from Steam will not work.
After closing out of the game, the number in the steam_appid.txt is reset to its default.
A full list of steam IDs are here: http://developer.valvesoftware.com/wiki/Steam_Application_IDs
Link to this comment:
All Comments (20)