Sorry to hear that Photoshop is not loading properly, could you try resetting the preferences of Photoshop and let us know if that helps?
Preferences Reset Photoshop - https://helpx.adobe.com/photoshop/using/preferences.
You may also try deselecting "Use Graphics Processor" located in Photoshop's Preferences > Performance, then relaunch Photoshop and let us know if it helps.
Thank you for the suggestions, Sahil, but...
I have deselected "Use Graphics Processor".
I have reset Preferences.
I can now open a photo, but the circle remains in the background, reappearing immediately when the picture file is closed, but while PS is still open. The Tool Bar also disappears when a picture file (just the file, not PS) is closed.
As a last-ditch effort, I am downloading all updates - up to 13%. Will post results.
have you got a graphic tablet by any chance?
i read issues with drivers giving such loading icon
try updating all drivers once you're at it
even video card
Not using a graphic tablet. PC is up-to-date. After updating PS, this afternoon, things are a bit better, so I will live with it for now, rather than wasting time on it. Windows 10 updated itself yesterday and I have a suspicion that it may have caused the problem. If things improve with the next Win update, I will post a message.