Some gamers in the U.S who used an online retailer in Thailand for their Orange Box product keys have had their copies of the game deactivated.

"Valve uses Steam for territory control to make sure products authorised for use in certain territories are not being distributed and used outside of those territories," Valve said in a press release.

"In this case, a Thai website was selling retail box product keys for Thailand to people outside of Thailand. Since those keys are only for use in Thailand, people who purchased product keys from the Thai website are not able to use those product keys in other territories."

To compound their misery, gamers who have bought new U.S copies of the title still can’t get the game to work and have been told to contact Steam as details of the Thai code remain in the system.

"Some of these users have subsequently purchased a legal copy after realising the issue and were having difficulty removing the illegitimate keys from their Steam accounts. Anyone having this problem should contact Steam Support to have the Thai key removed from their Steam account."