So I found a handy utility that has resolved this for me.

The program is called “SetUserFTA”

By simply running “setuserfta .txt applications\notepad++.exe”, the problem is fixed.

A link for the program description and download is found here.

http://kolbi.cz/blog/2017/10/25/setuserfta-userchoice-hash-defeated-set-file-type-associations-per-user/?sfw=pass1613420164

Additional details and instructions may be found here.

https://www.winhelponline.com/blog/set-default-browser-file-associations-command-line-windows-10/

I hope this helps my fellow Notepad ++ users!

Best Regards,

Terry Musser