How do I... Change file extension associations in Windows Vista?

Like Windows XP before it, Microsoft Windows Vista relies on a system of file extensions to determine which application will be called for a particular file. To change file associations, a user must navigate to the Set Associations tool. Mark Kaelin shows how it works.

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To determine which application will run when you double-click a file icon, Windows Vista uses the familiar file extension system made famous (infamous) in earlier versions of Windows. And just like the previous versions of the operating system, figuring out how to change a file extension association in Windows Vista can be a little frustrating if you don't know where to look.

The steps

The Windows Vista tool you use to change file associations in located in the Control Panel under the Default Programs icon, as shown in Figure A.

Figure A

Control Panel

Oddly enough, searching the "association" in the Vista search tool off of the Start Menu returns no results -- at least for me.

Once on the Default Programs screen you have two choices for changing file associations:

  1. Set your default programs
  2. Associate a file type or protocol with a program

You can also change AutoPlay settings for CDs and DVDs for this screen, as well as set program access settings. (Figure B)

Figure B

Default Programs

The first selection on the Default Programs screen (Figure B) is Set Your Default Programs. On this screen of the tool, as shown in Figure C, you can select a program and either give it complete control as the default program for all file extensions it can handle or choose the file extensions you want individually. How the list of programs was formed for this tool is not explained, but a few programs are missing from the list. The one program that comes to mind almost immediately is Adobe Acrobat Reader.

Figure C

Set Default Programs

Clicking the Choose Defaults For This Program option on the Set Default Programs screen (Figure C) shows you a list of potential file extensions that can be associated with the chosen program (Figure D). From here, you can check additional file extensions you would like Windows Vista to associate with the program.

Figure D

Select extensions individually

The second selection on the Default Programs screen (Figure B) is Associate A File Type Or Protocol With A Program. On this screen of the tool, shown in Figure E, you get a very long list of file extensions, including a description and the name of their associated program if it is known. To modify the program associated with a particular extension, you select the extension and click the Change Program button.

Figure E

Set Associations

In the example shown in Figure F, I have chosen the .inf extension, which is currently associated with Notepad. From this screen, I can choose to change the association to another available program.

Figure F

Change an extension association

If another viable program is not listed on the screen in Figure F, you can browse your system for programs (Figure G). Note that it is generally not a good idea to associate a file extension with a program that is not capable of reading or otherwise acting on it.

Figure G

Browse programs

Once your file extensions are selected, you click Save and then OK to apply your changes to Windows Vista.