Thanks for the response and your interest, Charles. I'm glad that all is o.k. for you.

My Mac Min, my several drives, my monitor and my home network were all working A-OK prior to my upgrading to Monterey.

As you have indicated you do, I avoid upgrading immediately to new software, particular a new OS. However, it had been several months since Monterey came on the scene and the option to which I responded gave no indication that it was a Beta release and the requirements said that my 2018 Mac Mini (32gb / 256gb / 3000 ghz) was suitable to run it. It seemed to offer so many advantages that I thought I'd take the leap. However, clearly I ought to have waited longer - I agree with you and it's a mistake that I hope I'll never repeat.

I can't say whether my issues would be resolved now because, as a result of my problems I decided to downgrade my OS - that, too, evidently was a major mistake.

The Mini would not longer start in Safe Mode nor Recovery Mode though I finally managed to get around that by downloading Big Sur separately and then attempting a new install.

When I did that, my computer locked and I was unable to use it at all. After calls to Apple and a visit to a local service agent, I discovered that, despite my Mini being registered under my Apple ID and my having password and all and having used it with a subscription to Apple Music & to Match and having purchased several products from the Apple Store, I could not get my computer unnlocked - even by the service agent if I showed them proof of my identity - without the receipt for the original purchase when new.

This is nonsense. Security gone mad. Yes, I appreciate Apple's care for user security - it is valuable & worthwhile - but really?

Although having been an Apple client since the Apple II & Hypercard, - a long time in anyone's book - I was raised in the slums and never affluent. All of my computers bar those I saved an bought for my children, have been pre-owned & usually several years and models old.

So - I have a 2018 Mac Mini - purchased as a pre-owned machine - with receipt from eBay and PayPal showing my name and address (which haven't changed in 20 years) but that is not good enough for Apple.

I was fortunate (!) because I was able to reach the seller, some 3000km away and after 3 years and he was brilliantly helpful and managed to obtain a copy receipt from where he'd bought the machine. [I'd suggest that; in many cases, one might be unable to reach the original buyer, that they may not cooperate anyway; that even if the were as kind as the person in my case, they may no longer have kept the receipt or be able to access one from the supplier.

The upshot was that I did finally get my computer unlocked and restored to an earlier OS. However, as well as the stress, it cost me almost 50% or my weekly income.

I apologise for this long response. However, in my original report of this in the submission to which you responded I mentioned only a few of the issues that occurred after my upgrade - in fact, the computer became as good as useless to me.

Yes, you may be right - the problem may be with me. All I can say is that with 50+ years of owning and using every type of Mac other than the latest silicon machines, as well as Windows and Linux OS machines and a Vax mini-computer, I do have some experience, though I claim no particular expertise.

I had a computer I was enjoying and that was working effectively. I back up with Time Machine and keep a clone copy of all my personal files on a separate hard disk. I run a password manager that stores locally; I use 2 factor verification wherever I can; I use minimum 16 character passwords with upper/lower case/numbers/symbols - unless the site won't allow it - peculiarly I have just had a hassle with a BANK which won't allow symbols and a LIBRARY whose It manager says 8 alphabetic characters is o.k. and won't allow any more. He even recommends on his site that it should be something you'll easily remember such as you child's name.... ! I run an anti-virus & malware check daily and have active anti-virus running in the background.

My point is, that I am reasonably sensible and careful, I think. [Perhaps I'm wrong}. Apple nowhere suggested that I may run into problems or that I shouldn't install Monterey on my Mini. On the contrary, they were pushing me via 'Updates' to do it.

So yes, it is probably my fault - in my life it seems everything is - but unfortunately I'm too stupid to understand why.

.... And no, I have no beef with your or your comment. I've just flown off the handle a little because, reading your comment just now brought it all back.

The simple and polite answer ought to have been: "Thanks for your interest. After some difficulty I downgraded my Mini to Big Sur. All has been o.k. since then save for having much re-setting and re-installing to do. I don't know if current versions of Monterey would be different because I'm no longer game to upgrade."