19 hours ago, NotHereToPlayGames said:

5) Type "cd " (c d SPACE) without the quotes then CTRL-V then hit ENTER.

You typed "cd", then (c d SPACE) which seems to be 2 separate commands. It failed both ways with error messages.  Sorry, I don't like command lines, too many ways to make a mistake or not understand the exact command.

20 hours ago, NotHereToPlayGames said:

6b) In that ADMIN COMMAND PROMPT, enter and execute the following INCLUDING the quotes around the .exe file name:
"PDFXEdit v6.exe" /fileassoc:user=no

6c) AFTER doing the above, do the BELOW in that ADMIN COMMAND PROMPT (this sets CURRENT USER registry configuration that is USELESS without the LOCAL MACHINE registry configuration also in place):
"PDFXEdit v6.exe" /fileassoc:user=yes

Whatever is easiest for you, OPEN AN ADMIN COMMAND PROMPT and direct it to the FOLDER CONTAINING your "PDFXEdit v6.exe".

Then perform BOTH of the following (unsure if which is performed first is important or not, this was the order the DEVELOPER indicated):

"PDFXEdit v6.exe" /fileassoc:user=no
"PDFXEdit v6.exe" /fileassoc:user=yes

This really really REALLY should solve your problem - IT IS DIRECT FROM THE DEVELOPER OF PDF-XCHANGE (but the VIEWER instead of the EDITOR, this method is supposed to work for both).

Edited December 17, 2025Dec 17 by NotHereToPlayGames

See here for more - https://help.pdf-xchange.com/pdfxe6/index.html?command-line-options_ed.html

I'm afraid that if you find command lines "too confusing" then I'm not going to be able to assist any further.

I've provided what the DEVELOPER HIMSELF/HERSELF cites for setting file associations.

^ Understood, I appreciated all the help, but I'm not a 'typist' and never really good at spelling and it aint getting any better.

But, the following worked;

Default Programs Editor

https://defaultprogramseditor.com/

Edited December 17, 2025Dec 17 by videobruce
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