Settlers 7, which many users (about 50 pages worth on this forum thread) are still unable to access two weeks after the game launched due to problems with Ubisoft's DRM authentication servers.
A Ubisoft rep commented on the issues to Eurogamer, explaining, "our technical teams have made progress but we are not yet able to say that the issue is completely resolved." Hey guys, take your time. Just keep letting that anticipation build up in your player base. Once they're finally able to play, we're sure they'll thank you for the extended expectancy.