File sharing between two Catalinas - Finder cannot connect So I can screen share between the two Macs; I can ssh, rsync, and scp  the files between the two Macs; but having Finder try to “Connect As” always fails the login sheet using the same user and password as on the command line. 

I tried switching between SMP, SMP encrypted, and AFP ... makes no difference. Authentication? Always fails. Shakes it head at User and password validated as above.  

Both Catalina systems were upgraded from previous OS X / MacOS versions, but both client and server accounts are new.
Regrettably I have found no solution to this anomaly. 
I was in the fortunate position to be able to erase and re-install Catalina.   

The problem no longer exists for me. I have a “de-crufted “ system.   

I’m always impressed by how OS X / MacOS has been able to upgrade this Mac successfully for about 6 years with very few of these kinds of anomalies encountered generally in upgrades over the last couple of decades and nearly a dozen different Macs.