For years I have attempted to connect to Windows 7 and 10 using the SMB/CIFS client in eCS with no luck. COTS Linux based network drives have worked.
Each machine is in the same workgroup and I have a common host list on each machine and the alias' do resolve for all other computers I have on the network.
When I tried this with Arca OS 5.0, it still did not connect which was disappointing, then I tried using the IP Address of the windows box and it worked.
I don't know why using the machine name works for other boxes except the Windows 10 one, the other names resolve just fine. I thought I would share this since it works and it may not be a solution people think of when trying to connect.