Yes, simple homegroup called workgroup. DHCP set on all equipment. Tested with 2 different routers, alone. Have gone and reset all sharing to none, on both computers.
Hard reset means, to me, total power off restart. will revise lingo to "cold" reboot (CR). All power sources removed/discounted.
btw..
Renamed computers names to match two of the names that I can't remove. They work and can RDP from both to ea. other.
I did a power on, complete restore to default setting on router, after shutting down pc's for cold restart for all. But both routers show the sames names I don't want.
So this rules out routers here, No? Before connecting to router (no wifi on it) wire only, I renamed the computers to names never used. Cold Reboot (CR) them, plug in to router.
I see new names and still three other names in the network workgroup. I see 5 pc's when only two exist on the lan.