Paulaner
Space Core
- Joined
- Aug 31, 2007
- Messages
- 1,945
- Reaction score
- 6
Well I have absolutely no idea.
It worked this way with Half-Life 2 retail for me: on installation the game required to have Steam running. Steam asked me for the serial number on the box and now HL2 is on my Steam list. As a matter of fact, retail versions of Valve games are sort of Steam backups.