This game seems to have problems on any system newer than XP. It installs if you're lucky, but never starts and refuses to patch no matter how much you try.
So far I have only found one way around it and that is to install the game on XP, patch it, crack it, and copy the folder to a flash drive to play, or copy it to a machine running Vista/Win 7.
If you want to go through that process, here's what to do.
1. Install the game from the cd on a XP machine.
2. Download and install the patch:
Mirror 1: http://www.megaupload.com/?d=G9TLDG14
Mirror 2: http://www.4shared.com/file/hupZdnKk/Indigo_Prophecy_Patch11.html
Mirror 1: http://www.megaupload.com/?d=1TY6L6BB
Mirror 2: http://www.4shared.com/file/D_UUFfJr/Fahrenheit_Patch1_1.html
3. Download the no-cd crack:
Mirror 1: http://www.megaupload.com/?d=DFQGJGZC
Mirror 2: http://www.4shared.com/file/SM9ckiy8/IndigoProphecyCR.html
Mirror 1: http://www.megaupload.com/?d=5R73D7N0
Mirror 2: http://www.4shared.com/file/zOqhOq5d/FahrenheitCR.html
4. Go to the game's install directory (usually C:/Program Files/Atari/Fahrenheit/) and replace the game exe with the one in the zip.
5. Copy the Fahrenheit folder to a flash drive.
Alternatively you can download this:
It has been patched and cracked already. There is a reg file in there, just in case the game doesn't run, but its only rarely that it is needed. Just extract to wherever you want and play.
It is the EU version. Don't know if thats important, but thought I'd mention it anyway.