[FIXED] how to fix PK3 files?

[simpletonnn]

i may or may not have accidentally set the PK3 files to open in Windows Explorer and i cannot change it anymore (i understand that i can still use Open with to use the source port but it's more convinient when it's already ran through it )
is it possible to fix? if so how do i do so?

[Titan314]

Right click on a pk3 and click on "open with". Make sure that "Always use the selected program for this file type" is checked.
Click on zdoom. If it is not in the list, click browse and find zdoom's executable.

[simpletonnn]

Right click on a pk3 and click on "open with". Make sure that "Always use the selected program for this file type" is checked.
Click on zdoom. If it is not in the list, click browse and find zdoom's executable.

the problem is, i cannot set zandronum as the default program because the option to set the default program is greyed out.
and, supposedly even worse, i can't find PK3 files as a filetype in Set Associations

it seems that when i accidentally opened those files in windows explorer, windows treated them as file folders. but even so, when i try to open them the computer just freaks out.
EDIT: PROBLEM IS FIXED, DELETED .PK3 ASSOCIATIONS THROUGH REGISTRY