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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.