To edit a file association, follow these steps:
1. Choose Start | Control Panel, click Appearance And Themes, and run Folder
Options. You see the Folder Options dialog box. (You can also display this
dialog box by choosing Tools | Folder Options from any Explorer window.)
2. Click the File Types tab.
3. In the Registered File Types list, click the type of file you want to
associate with a program. (Scroll down the list--it's long.) When you select
a file type, more information about that file type appears in the Details
For File Type box. You also see two buttons: Change (to associate one
program with the file type) and Advanced (to associate multiple programs
with the file type).
4. To see or change which program Windows runs to open this type of file,
click Change. You see the Open With dialog box. Select the program to run or
click the Click Here link (in "If the program is not in the list, click
here") to find the program file. Then click OK. Close the Open With and
Folder Options dialog boxes.
Windows now knows to run the program you specified when you open a file of
this type.