masterkd
Padawan
Yeah, backup and restore is another thing.
Let's say I have the retail version of COD4 installation disk (non-steam installation disk). Now I purchased it on steam and I don't want to download everything again. Is there any way around this?
This can be done on Origin. I have a retail disk of Burnout Paradise and later I got the game in one of the Humble Bundles (the EA one). I installed the game from the disk on my PC (non-origin installation) and then copied the files in game directory to another folder. Then I uninstalled the game. After this I started downloading the game in Origin and paused it after a few minutes. Then I closed Origin and copied the gamefiles into the Origin directory. After opening Origin again I started the download and it started from around 90%. It downloaded only the patches and leftover files.
Is there any way to do the same in Steam?
Yes you can do this for steam as well. Just make sure you paste the files in right folder in steamapps when steam is not running. After copy-paste is done, verify integrity of game cache for that particular game and you are all done. If any update/download is required steam will do automatically.