2012 w Nav/Entune Suddenly "System Not Installed?"

The Display Audio w Nav & Entune has worked fine for over 5 years. Yesterday when I pushed the "Apps" button, I just get an overlay that says "System Not Installed." The display works, radio is fine and so are all the "Car" info screens, but no apps. And when I went to make a call, it says I don't have any phones paired, even though I've used bluetooth phone hundreds of times. And I plugged my phone into the USB port to charge and hoping it might wake up the apps - no luck, and it didn't even charge the phone (so port is disabled?).

No one has done and work on the car and nothing was changed - first thing everyone asks.

I called the local dealer and (of course) they've never heard of the problem, and didn't have any openings until next week. I called Toyota USA tech service and they were going to suggest I reinstall Entune but said I can't if the USB port isn't working. I was going to try it anyway, but I could not find a download file online??? So they said take it to the dealer...

I found several other owners who've had the problem but few answers. One said they were told they needed a new "control box" at $1600.

Anyone here who can shed any light on this issue?