Windows 2003 Server crashes - due to permissions??

Hi! We're running Windows 2003 Server with SP1 and all updates in place. Something is dreadfully wrong and I've found nothing at Microsoft, nor have I found any listings on the internet for anyone else with this problem. It goes like this.

If *ANY* User/Group other than an adminstrator attempts to rename certain folders and files (our files, not system files), the server crashes (stop error)and reboots.

Bugcheck String: 0x00000019 (0x00000020, 0x88f46d88, 0x88f46e58, 0x0a1a0003)

If logged on via network as Administrator, I am able to change the file without a problem?! Does this make it a permission handling item? Could I reinstall a .dll file or another file to fix it? Can I provide more information that would help?

Thank you!