I guess I'll get straight to the point: My Steam version of Assassin's Creed 3 suddenly stopped working a couple weeks ago.
In case some of you are not familiar with the Steam version: To start the game, I actually click "Play" on Steam, which launches Uplay.
Uplay then checks updates and so on and eventually starts the game.
First of all I can say that my PC, as well as my OS (Windows 7) don't pose any problems, as I was able to play around half to three quarters of the game without any problems and without frame rate drops.
So this discussion will probably not be about hardware.
The thing is that one day (without even tempering with any game files or installing any new software) the game would no longer launch.
After clicking "Play" on Steam, Uplay would be started (as it's supposed to), checking for updates and the cloud for my savegames and THEN the actual game is supposed to start - this is the point where nothing happens!
The "Play" button on Uplay grays out and when I check my task manager, there is even an entry for the game, however the game itself just doesn't appear/start up!
When I end the process through task manager, I get the usual screen that shows me my Uplay points and the time I have "played" (depending on how long the process was running).
I can then click the Play button on Uplay, but that just causes the same problem: Nothing whatsoever happens!
So, I tried ANY possible solutions I could think of: I started Steam, Uplay and the game itself as Administrator, I set the compatibility mode of the game application to Windows XP (which I found out to be useless, since the game wouldn't support XP anyway) and I completely deinstalled Uplay and the game and downloaded it once more on Steam - with no positive effect, the problem remains!
One thing I tried was to validate the game files on Steam and the game actually started up again. So I was happy, but as it turned out only for one night, because the next day the problem was back and validating the files through Steam never helped again.
Although I must admit that Steam do gives me a message each time saying that 1 corrupt file needs to be reacquired, which it then supposedly does...
Long story short: Game worked perfectly for weeks, but suddenly would no longer start up!
I have searched Google plenty of times and none of the message boards I found could deliver any answer as to what may be the problem.
So I registered on the Steam forums (since it's Steam that I bought the game on), but apparently it takes their mods weeks to activate accounts... So I thought I might as well ask the Ubisoft community.
I am desperate, because I really enjoyed the game and was planning on finishing it before the release of AC4: Black Flag, however I ran out of any possible solution I could think of.
I hope that at least someone here can come up with a solution to my problem and any suggestion would be greatly appreciated!