When you right-click a registered file type, you can use the Open With command to select a program to open the file. Each program you use is added to the Open With list for that file type, even if the program you are using is unable to open the selected file type. For example, if you select Microsoft Paint (SPaint.exe) in the Open With dialog box when you open a text document (a file with a .txt extension), the Paint program is listed in the Open With list for all text documents, even though Paint is unable to open text documents. This article describes how to remove programs from the Open With list.

WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.

The programs on the Open With list for each file type are independent of that file's registered program(s). To remove items from this list, locate the following registry key NOTE: The above registry key is one path, it has been wrapped for readability.

where extension is the file extension for the file type whose Open With list you want to modify. Delete the value in this key that represents the program to be removed from the Open With list.