Between the XBOX forum and the Microsoft forum, it seems everyone is reporting this problem. Mine just started this morning with the Daily Challenges. They must be aware of this by now if you look at the number of people reporting. I am not going to restore my computer, as they suggested, I don't believe it is my computer judging from all these comments. I have only had Windows 8 since Jan. This is the first problem I have had with the XBOX games. But the Microsoft forum has people stating that this is not the first time it has happened.