How to Change Windows File Extension Associations

A Microsoft Windows file extension association determines the program used to open a particular file type (such as Microsoft Word opening ".doc" files). Although most system and Windows-specific files should not be changed, there are associations it can be useful to edit, such as MP3 files or other multimedia. You can easily change your file extension associations in Windows XP and Vista.

Instructions

Windows XP

1. Click on "My Computer" ("Start >My Computer," or use a desktop icon).

2. Click "Tools" on the menu box. Click "Folder Options," and then click "View."

3. De-select the box next to "Hide extensions for known file types," and then click "OK." This will allow you to view file extensions.

4. Locate a file with the extension you want to change an association for. If necessary, click "Start>Explore" to locate a file with the extension in Windows Explorer.

5. Right-click on the file and select "Open With." Select the program you want to associate with the particular file extension. Check the box next to "Always Use this Program," and click "OK."

Windows Vista

1. Click on your start menu and select "Default Programs."

2. Click on "Associate a File Type or Protocol with a Specific Program." Wait for the list of extensions to populate (this may take a few minutes).

3. Use the scroll bar to find the file extension you want to change the association for. Click on the extension, and then click "Change Program."

4. Select the program from the list, and then click "OK."

References

• Microsoft XP Support: How to change or select which program starts when you double-click a file in Windows XP
• Microsoft Vista Support: Change which programs Windows uses by default