Windows File Protection

A common problem in the history of the Microsoft Windows operating systems has been the ability for shared system files to be overwritten by non-operating system installation programs. After such changes are made, the user may experience unpredictable system performance, ranging from application errors to operating system crashes. This problem affects several types of files--most commonly dynamic link libraries (.dll) and executable files (.exe).


In Windows 2000 and Windows XP, the Windows File Protection (WFP) feature prevents overwriting or replacement of certain system files. Overwriting shared system files can result in unpredictable system performance that ranges from application errors to operating system crashes. System instability caused by non-standard replacement of system files has been a common problem. By preventing the replacement of these essential system files, file version mismatches are avoided, and the overall stability of the system is improved.