Windows auto lock down

I have a Windows 2000 computer that is locking itself about every 5 minutes. I have checked the screen saver setting and it is not set with password protect, and I have gone into the power settings and it is not set to prompt for a password. This computer did have spyware on it and I have cleaned it up. when a different user logs in, it does not auto lock. I’m wondering if it is a registry setting or what, I am lost as to where to go. Please help me! Thanks