Far Cry 3 has launched in Europe and Asia on Steam, and it's currently available for download through the service. Players who've bought the game early have reported that they have been unable to play the game because of Ubisoft's online service, UPlay.
The service is one Ubisoft uses in all of its games to offer players additional in-game rewards for committing to Ubisoft titles. It used to double as DRM in the company's games until players complained about its functionality, which required players to remain connected to the internet while playing single-player games on the PC.
An article on Rock Paper Shotgun extensively details the problem that players are currently having with the service.
Ubisoft was quick to acknowledge the problem on Twitter, and stated that the company is working on a fix to get the servers back up and running.
Thankfully, you don't have to wait for them to release a fix to play the game. You can completely bypass UPlay by setting the service to 'offline'. Unlike Ubisoft's previous games, UPlay isn't implemented as a DRM layer, so you can safely play the game in offline mode without impacting your save files.
If you're having trouble with Far Cry 3, just do that. It won't eat your save files, we promise.