How to Show or Hide File Name Extensions in Windows

A filename extension is an identifier specified as a suffix to the name of a computer file.

The extension indicates a characteristic of the file contents or its intended use.

By default, Windows Explorer hides file name extensions in Windows Operating System. However, you can make file name  extensions visible.


  1. Press How to Show or Hide File Name Extensions in Windows 7W6b39o keys.

  2. Type C:\Windows\System32\rundll32.exe shell32.dll,Options_RunDLL 7 into Run dialog box and click OK button.

    How to Show or Hide File Name Extensions in Windows IK1FaqQ

  3. From View tab scroll down until you notice Hide extensions for known file types, un-check this line by clicking the check box.

    How to Show or Hide File Name Extensions in Windows QujnpPM

    Note: To hide file name extensions, check this line.

  4. Click Apply and OK buttons.