How to Show File Extensions in Windows Using Regedit

By default, Windows hides file extensions for recognized file types, which can obscure the true format of files and create potential security risks. This guide provides a direct, step-by-step walkthrough on how to force Windows to display all file extensions for known file types by modifying a specific entry in the Windows Registry using the Registry Editor (Regedit).

Step 1: Open the Registry Editor

  1. Press Windows Key + R on your keyboard to open the Run dialog box.
  2. Type regedit into the text box and press Enter or click OK.
  3. If prompted by the User Account Control (UAC), click Yes to allow the application to make changes.

Step 2: Navigate to the Explorer Advanced Key

In the Registry Editor, use the left-hand navigation pane to browse to the following path:

HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced

You can also copy and paste this complete path into the address bar at the top of the Registry Editor window and press Enter.

Step 3: Modify the HideFileExt Value

  1. With the Advanced key selected in the left pane, look at the list of values in the right pane.
  2. Locate the DWORD value named HideFileExt.
  3. Double-click HideFileExt to open the Edit DWORD window.
  4. Change the Value data from 1 (hidden) to 0 (visible).
  5. Ensure the Base is set to Hexadecimal, then click OK.

(Note: If the HideFileExt value does not exist, right-click an empty space in the right pane, select New > DWORD (32-bit) Value, name it HideFileExt, and set its value to 0.)

Step 4: Apply the Changes

For the changes to take effect across your system without restarting your computer, restart Windows Explorer:

  1. Press Ctrl + Shift + Esc to open the Task Manager.
  2. Under the Processes tab, find Windows Explorer.
  3. Right-click on Windows Explorer and select Restart.

Once the process restarts, all file extensions (such as .txt, .exe, or .docx) will be visible in File Explorer and on your desktop. To revert this change in the future, return to the same registry key and change the HideFileExt value back to 1.