Change file association back to unknown program in Windows 10

Hi,

Thank you for posting in Microsoft Community.

We understand how you feel about the situation. We're sorry for the trouble.

I suggest you to follow the below steps and check if it helps.

1) Create a new file with any extension and save it on any location.

2) Next Open Control Panel (icons view), click/tap on the default programs icon.

3) Click/tap on the Associate a file type or protocol with a program link.

4) Either double click/tap on the file extension or protocol, or click/tap on the file extension or protocol and click/tap on the Change Program button of the one you want to change the "current default' program association of.

5)  If the program you want to associate is not listed, then click/tap on the More Options link if available.

6) Click/tap on a listed program that you want to associate.

7) If you associated a program, then you will see this below as "Set Associations" updates and reloads.

8) Once it is done go back to the file which you have created and delete the file.

9) Go to default programs and refresh the set association programs. It should show as other unknown.

Hope this helps. Please reply to us with the status of the issue.

Thanks.

We have looked further into this and found a similar thread with a solution.

Please see this link.

Regards.