Role-playing title Mass Effect is set in a far-flung future
Microsoft has apologised for the glitches that hit its Xbox Live online game system during the Christmas break.
The software firm said it was "disappointed" with its performance and promised a free downloadable game to all users as recompense.
It said the problems had been caused by a surge of people signing up and using the gaming service.
Microsoft said the growth in new users had been driven by sales of top titles such as Mass Effect and Halo 3.
The Xbox Live service suffered an ongoing series of problems during the holiday season. The discussion boards and forums of many gaming news websites have been filled with gamers complaining that they could not sign up or get on to the service.
Writing on the Major Nelson website, Marc Whitten, general manager of Xbox Live, apologised for the "intermittent" service.
"While the service was not completely offline at any given time, we are disappointed in our performance," he said.
He added the outages were driven by a record-breaking number of new members signing up, and the biggest ever number of concurrent users. Most Xbox Live members pay an annual fee to use the service.
As a reward for their patience, Mr Whitten said all eight million members would get access to a full Xbox Live Arcade game free of charge. Details of how to claim this game would be made available in the next few weeks, he explained.
The downloadable games on the Xbox Live Arcade typically cost up to $20 (£10).
The Xbox Live service lets owners of Microsoft's gaming console take each other on or help each other in games, and allows them to download lots of games and watch TV shows and films.