The Mac I am using is the one in my profile. I answered your questions; here they are again.
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Mar 5, 2019 1:17 PM in response to ProbsRus
The USB ports are working for everything except the keyboard on the back of the iMac. Yes, its the iMac I said it was on, and the Bluetooth mouse has a dongle that plugs into a USB port. And yes its a brand new keyboard purchased today. I'll try the NVRAM links above & report back. thanks all.
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I just bought the keyboard yesterday at the apple store, I can't get any more specific, so I go grab the thing to see if there is a model number, and there I see on the back a little switch on the right that turns the keyboard on and off.
not sure why apple would add an on/off switch to their new wired keyboards, that also have a lightning connector now, no cord sticking out the back.
I solved my own problem.