Great advice guys, and I wish I had come back here to look first, but here’s what I did:
Contacted Norton Support and worked with them online and they turned Norton off. Nope.
Then they completely uninstalled Norton, and the problem remained. So, not the anti-virus.
Norton reinstalled, and then I thought about it for a while.
It occurred to me that one of the things I had tried was “Reimport Old Content Database” (I’m probably not getting the wording correct on that, but I’ve got a render working right now, so DS is not accessible at the mo.) and when I tried that I kept getting an error.
Suddenly I had a “forehead slapping” moment. The old content database was corrupt, so DS couldn’t read it or rebuild it (duh).
Scanning the C drive for “database” led me right to the file you mention, which I deleted.
Fired up DS and then proceded to follow Jade’s instructions again and voila! 4 hours later (I’ve got a lot of Content. LOL) my Content Library/Products and Categories lists were all back, including my precious Smart Content.
As to why I didn’t save myself all the trouble I went through instead of coming back here first?
The past 2 days were some long days at the Dr’s office, followed by long periods of similar RL stuff.
I did the Norton stuff and the rest in my spare time before getting back to the DAZ threads tonight.
I’ll change the title to reflect that the solution to this particular problem is contained herein.
A BIG thanks to all who took the time to help me!