When I assign specific file extensions to default program it doesn't hold

[videobruce]

Yes, I know how to do it (all 3 methods) but when I point to the programs .exe it doesn't 'stick' in the dialog box. I've done it multiple times, same thing. It's like I never pointed W7's O/S to anything. This just stared a few days ago. No real idea what caused it. Specifically it is .pdf files, but document files were affected also, but for some reason I was able to re-assign that file type.

To make matters worse, I even went to the hassle to restore a image of the O/S I made almost 3 months ago and the same same thing!!
In fact, it was more than one type of file, but .pdf is the major issue.

When I choose the program, the pop-up box with all the other 'assigned' programs shows, but the one I tried to add doesn't get added to the list.
It's PDF Exchange (that I have used for years) is the specific program, but again, it's ALWAYS worked with NO issue. This image and what was the former current active version.

Again, any way I do this it fails. Then and now.

One more detail, I also lost the default programs for .txt (I use Notrebook2) and .odt (Open Office documents & Spreadsheets), but I was able to restore those.
All of this happened apparently one time again, in both W7 installations.

[videobruce]

This will help; after I click on the .exe, nothing happens, no error messages etc.

 

[NotHereToPlayGames]

I'm not familiar with "PDF-Xchange", but your screencap cites it as PORTABLE.

So what happens if you copy the folder (archive it somewhere), then DELETE the portable apps "profile" then launch it?

Just speculating as all of my portable apps have their own "bin" (profile) where files and registry is saved within itself (as opposed to Win Registry / Program Files Folder / User Data Directory / etc).

ie, force PDF-Xchange to start BRAND NEW / FIRST-RUN.

Edited 1 hour ago by NotHereToPlayGames