How can I change or fix an association of a .dll file in Windows 7?

Joeri December 31, 2011

I need to remove/undo the association (notepad) for a .Dll file.

I’ve successfully followed these steps:
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\FileExts\[fileextension]\OpenWithList. and deleted the unwanted file.

Then I checked the Recommended Program List for .Dll file. But the unwanted program was still there in list. So I thought changes might be reflected after reboot. But even after reboot it was showing the program in list.

I’ve again confirmed that key is deleted. So what’s wrong?

    January 2, 2012 at 6:44 am

    Hello, when you navigated to path in your post and found the .dll file, did you find a UserChoice entry in OpenWithList?  If you did, you could delete that entry and restart system.  That should set back your default extensions for .dll. 

    If the Userchoice file doesn't show there, you could try to unassociate the file type, by using the procedure recommended in the link below.  As usual when you are making changes like this, it is important to backup your registry and also the registry entry you are changing:

    Once you have run process shown in link, try to run the file provided in previous comments to fix the association problem.  As another option, you could try running the sfc /scannow command in command prompt. 

  2. Anonymous
    December 31, 2011 at 10:11 am

    Iphone backup extractor, try it with trial version with your reponsibility and see if it can help you

  3. Jeff Fabish
    December 31, 2011 at 3:06 am


    Please download and run this registry file. That should fix it.

    - Jeff

    • Joeri
      January 1, 2012 at 9:04 pm

      I tried it already and dident worked, I think I almost tried everything, I know it doesnt affect the file itself but still the notepad association remains.. :) Thank you