Remove applications from the Open With List in Windows Explorer

Sometimes your Windows Explorer's Open With list can get cluttered with applications that don't match the file they are associated with. Mark Kaelin shows you how to fix that.

During the normal course of activity, the Open With List associated with a particular file type in Windows Explorer can get cluttered with applications that really don't apply (Figure A). Most of the time we ignore these extra entries, but you can remove them with a simple registry edit. A clean Windows Explorer is a happy Windows Explorer.

Figure A

Opening a PDF file with Notepad is not useful -- let's remove it.
This blog post is also available in PDF format in a TechRepublic download.
Note: This Quick Tip involves an edit of the Windows Registry file. This file is vital to the operation of the Windows operating system and could render your system inoperable if corrupted. Back up the file before you perform any edits.

This Quick Tip is shown using Windows 7, but the technique should be similar for Windows XP and Windows Vista.

Remove associations

First, start the Regedit application by opening the Start menu and typing regedit in the search box. Click on the regedit.exe file in the resulting list and answer any UAC prompts.

Navigate to the following key:

HKEY_CURRENT_USER \Software \Microsoft\Windows\CurrentVersion\Explorer\FileExts\

Then scroll down to the file type extension that you would like to edit. In our example, that would be the .pdf entry, shown in Figure B.

Figure B

Edit the .pdf file extension.
Click on the OpenWithList folder to reveal the various applications designated as applicable to that particular file type extension, as shown in Figure C.

Figure C

These are the applicable applications for the file type extension.
Right-click on the offending key entry you would like to remove from the OpenWithList and then click the Delete menu item. In our example, that would be NOTEPAD.EXE (Figure D).

Figure D

Right-click the Notepad entry and click Delete.
You will get an ominous sounding warning dialog box (Figure E) warning you about deleting keys in the Windows Registry file. But you backed up your file, so this should not concern you -- right? Click Yes.

Figure E

Click Yes to confirm you want that key deleted.
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Close Regedit to complete the process. Now, the next time you look at the Open With menu entry for PDF files you will not see Notepad as a choice (Figure F).

Figure F

Notepad doesn't appear in the Open With List for .pdf files anymore.