I was prevented from updating because my "product activation key is blacklisted", so I was somewhat p****d off. Then I was prevented from running Parallels at all. so now I am f*****g incandescent that Parallels have deactivated my PC spontaneously, without warning and without reason. Furthermore, it being the weekend (and I have client work to do) I wonder whether their support will solve this, or be away enjoying themselves on the weekend. We shall see.
Hats off to Parallels for dealing with this on the weekend. The Live chat is 24/7, and the Twitter account even responded although they say they are Mon-Fri. Here's what I think happened... When I tried to check for updates to PD8 it refused to download the update because it didn't think I was registered. I was registered, but since I reinstalled it a while back, I had not registered a second time. Anyway I pasted my product key into the activation field, and it all went badly wrong from there. When PD8 was first released, I upgraded immediately and couldn't get it to work properly on a MBPr, so they gave me a refund and I waited for a few more updates before risking the upgrade. And it was the old activation key that I pasted in. Doh! But I think this was at least partly caused by Parallels' rather twisted activation and registration requirements. I mean, this could not have happened with MS Windows activation: (a) it would have been completely clear that a valid activation code was in place, and in order to change it, I would have had to click on "Change product key", and (b) MS updates do not require registration as well as activation. Furthermore, the message, that my code was blacklisted was somewhat misleading. If for example, it had said that the code had been deactivated due to a refund, I might have twigged. But anyway, it is fixed.