·Did you make any software or hardware changes on the computer prior to this issue?
·What exactly you mean by ‘locked in Windows Media Center’?
·Which operating system you are using?
Let’s follow these methods and check if it helps.
You may also boot the computer into ‘safe mode’ and check if the issue persists. It will start Windows XP with a limited set of files and drivers. Startup programs do not run in safe mode, and only the basic drivers needed to start Windows are installed,
follow the steps to boot the computer in safe mode: