What is a system file?

A system file is any file on your computer that is essential for running Windows properly. System files are usually found in the Windows or Program Files folder.

Normally, you should not change system files by renaming, moving, or deleting them because doing so could prevent your computer from working properly. Even if changing a system file does not seem to have an immediate effect on your computer, the next time you start Windows or run a particular program, your computer might not work correctly.

If you need to make changes to your system, you should use a tool designed for that task. For example, to remove a program from your computer, use Programs and Features in Control Panel.

Open Programs and Features by clicking the Start button Picture of the Start button, clicking Control Panel, clicking Programs, and then clicking Programs and Features.