I am in the process of migrating file server from Windows Server 2012 R2 to Windows Server 2019. Previously I used Robocopy for this purpose. Windows storage migration is a neat extension provided by Windows Admin Center. I tested in my lab and works great. However, there are few requirements – Windows Management Framework 5.1, allow through the firewall, Enable PsRemoting

The issue I ran was when adding Windows Server 2012 R2. I allowed through the firewall, WRM service was running. PSRemoting was enabled. The error I was getting while trying to add the server in the WAC as well as when trying to initiate Enter-PSsession -computername w2k12r2server.
“WinRM cannot complete the operation. Verify that the specified computer name is valid, that the computer is accessible over the network, and that a firewall exception for the WinRM service is enabled and allows access from this computer. By default, the WinRM firewall exception for public profiles limits access to remote computers within the same local subnet”.

Resolution:
Netsh http show iplist

IP addresses present in the IP listen list:
-------------------------------------------

127.0.0.1
::1

On the working server, the list was empty. I had to delete both the address from list using:

netsh http delete iplisten ipaddress=127.0.0.1
netsh http delete iplisten ipaddress=::1

After removing the above address, I was able to add the Windows Server 2012 R2 to the WAC and also I was able to PSremote to the server.