So...The main EDLaunch.exe (provided with the installer on the PC - NOT Steam) started working again and I could log into both accounts. Same usernames and passwords. I don't know why and with Forum, Google, Reddit and YouTube searches there are no answers as to why going back as far as 2015. Oh well.
I then created a EDLaunch01.exe for the main account and EDLaunch02.exe for the explorer account in the EDLaunch folder.. 01 main works while 02 explorer fails with invalid credentials. Still my last login with the main launcher was the explorer account and it works. For now I have EDLaunch01.exe for the main and EDLaunch.exe for the explorer.
I'm looking to get EDLaunch02.exe explorer working with the main launcher as a backup. It has worked with many previous updates. I also performed Validate Game Files and started with and without administer privileges. As both accounts are in the single ED game installation on the PC I doubt that I could fly both at the same time nor would I want to. I've never tried. Still close the launch window and start up another who knows?
I have a help ticket but thought to update this thread as the problem is resolved. Sometime in the future a player might search for the same problem. That helps them and maybe even the Help desk. A player probably won't have access to my help ticket and all of us players are pretty much constant Beta testers in this game.
The worry is that with the upcoming update this week we get to do this all over again. Welcome to Elite Dangerous.
Meanwhile Sir.TJ....Love 'ya and it is NOT your fault!
Regards to All