[networking] The RPC server is unavailable. (Exception from HRESULT: 0x800706BA)

I had the same problem when trying to run a PowerShell script that only looked at a remote server to read the size of a hard disk.

I turned off the Firewall (Domain networks, Private networks, and Guest or public network) on the remote server and the script worked.

I then turned the Firewall for Domain networks back on, and it worked.

I then turned the Firewall for Private network back on, and it also worked.

I then turned the Firewall for Guest or public networks, and it also worked.