Password does not meet password requirements

Hi all,

This one has got me stumped.

Have been running my stand-alone windows 10 box ever since initial release and up to 1803 my box has always been running with the following setup:

• my system is a stand-alone Windows 10 PRO box in a Workgroup, not a Domain member
• my day-to-day account is a local account (NOT MS account!); I don't use a MS account (at least not one that I myself have consciously set up!!) for any apps like the mail-app, or Onedrive, or anything else.
• a second local account is present that is only there to have a second local account available. Not used for day-to-day.
• my day-to-day local account has ALWAYS had a non complex password
• there is NO password policy set (according to gpedit), so it reads:

---password history = 0 passwords remembered

---maximum password age = 42 days

---minimum password age = 0 days

---minimum password length = 0 characters

---password must meet complexity requirements = disabled

---store password using reversible encryption = disabled

Now the other day I upgraded my system to 1809 using the ISO from the Microsoft site and that looked OK. No errors or the like during upgrade.

Then the first thing that got me stumped was that all of a sudden the logon after the upgrade came back telling me I need to change the password. So silly me thought, just set it again to what is has always been, but now it tells me: Password does not meet password requirements

So gave it a complex password so I could at least get into my system.

Since then I have been trying to get my 'old' password setup again, but EVERY WAY I used in that effort always comes back with that (paraphrased) message. Not via Ctrl-Alt-Del, not via netplwiz, nothing. Creating a new user is a 'no-go' also. Still complexity required.

It is not a matter of blanking my password, I know how-to.

I simply want my non-complexity password back. 

A few posts I found on the net did not help (maybe I didn't find the right one?) and some 'helpfully' suggested to do a clean install.

I'm using a ton of installed business and productivity applications and utilities, so clean-install (and then re-installing/configuring all these applications  is not an option.

Does anyone here have any idea: 

• what <Removed> is going on here or why this behavior is occurring
• how to solve the 'apparently no password policy set' yet 'password policy still enforced'

Thanks for your thoughts and insight.