Hi Eric, thanks for taking time to help! I do back up, every Sunday!
However, before I do, as you suggested, I just found the 2 favorites screen savers, Cosmos & Beaches,
here: My HD>System>Library>ScreenSavers & found these: Beach.slideSaver and Cosmos.slideSaver, there are several others, as well, but none of them show up as options, when I go to SystemPrefs>Desktop/ScreenSaverScreen Saver Options is greyed out.
However, if I select Classic, in Slideshows, (not in ScreenSavers) the Source button is re-activated & I can select Cosmos (yay!)but Beaches, is still not available, here.
Just trying to learn more about how it all works, to avoid making whatever mistake, I made, which caused Cosmos to vanish. Now, that I found it, I'm not sure I want to do anything else.
Please, clarify your instructions; "restore that folder" to which location? Can I simply drag it to the location or do I need to make a copy, first.