It looks like thousands of gamers may have been cut off from the Xbox Live online gaming service, for changing their consoles to play pirated games.
Microsoft said it had banned "a small percentage" of the 20 million people who use the service. Online reports say up to 600,000 people have been cut off.
Microsoft, the company behind Xbox Live, said modifying a console is against the rules of the service.
The company haven't said how it was able to choose which gamers to ban.
Reports suggest that the ban does not stop the console from working and only affects a gamer's Xbox Live account.
It's thought video game piracy costs games makers as much as £740m a year.