Microsoft's artificial intelligence (AI) program, Tay, reappeared on Twitter on Wednesday after being deactivated last week for posting offensive messages.
However, the program once again went wrong and Tay's account was set to private after it began repeating the same message over and over to other Twitter users.
According to a Microsoft, the account was reactivated by accident during testing.
"Tay remains offline while we make adjustments," a spokesperson for the company told CNBC via email. "As part of testing, she was inadvertently activated on Twitter for a brief period of time."