So I download the Application Manager and run that. This brings up a subsequent message: "Installer failed to initialise. Please download the Adobe Support Advisor to detect the problem".
So I search for the Adobe Support Adviser and find that this program has been discontinued. The info I dig up is:
"The Adobe Support Advisor has been discontinued
The Adobe Support Advisor tool was used to analyze installer log and system information associated with installation errors. The tool has been replaced with improved installation support mechanisms. Please visit Adobe Support section for Knowledge base articles around Installation."
So I visit the Adobe Support section but this has no information on my specific problem and no contact information for any techies working for Adobe so here I am at the forum relying on the goodwill of other users of the program.
I am runnning windows 10, never had problems before. Computer is fast and untroubled by demanding graphics. Last updated photoshop a couple of weeks ago and it had been working fine up until yesterday. The messages indicate to me that its not a problem with photoshop itself but the Application Manager. Any ideas anyone?