Older versions of some games maybe, Medieval 2 has steam built into it from the start. You have to have it registered on steam to even play the game to begin with.Kargathia said:Older versions aren't. I still have a physical copy that only uses a locally checked CD-key, and in all likelihood pre-dates Steam.
Read above. There's no reason what you described would work, steam does not generically support every game ever made for no reason. But some games, like all of those made by Valve and various others who signed on for it as a form of DRM, like Medieval 2, are not only supported by it but require it.Soviet Heavy said:Its not that simple. Not all games that are on steam have the option to input your CD-Key. For example, I bought the Dawn of War Platinum Edition in stores, but only the vanilla game and Winter assault worked, while Dark Crusade wouldn't install due to a faulty disk. I tried to put in the Dark Crusade CD Key on steam, only to find out that its CD Key format was not supported
Edit:
Seems you (the first guy I quoted) may be correct and I have my timeline wrong. It does appear possible that Medieval 2 may not have required Steam from the start. However, it does appear Steam will support keys sold prior to that happening.