I set up a static IP address (via IPV4) on PC # 2 at home, to address an oracle issue on that machine.
That seemed to go ok, but now I can now longer RDC into PC # 2 from PC # 1, which previously I was able to do when it had a dymanic IP address. I get the standard "Remote desktop can't connect to the remote computer for one of these reasons [etc. etc.] I've re-booted both machines. PC # 1 can read the files on PC # 2 via the network, and both are on the same Homegroup . . .
I set the static ip address as 192.168.1.55, to insure I'd never have a collision with other devices.
PC # 2 definitely allows RDC.