UPDATE: I also downloaded and installed Muse and Premiere.
Muse works, Premiere, Photoshop and InDesign do not.
There were older CS6 trial versions of Premiere, Photoshop and InDesign installed on this computer. I deleted everything before I installed my subscription software.
Could that be related to something?
Your support in the other thread solved the issue.
Rename Common Files\Adobe\SLCache folder and then run any program as administrator.
As I said, you are a star! Thank you.