The Problem
On newer Macs the SMB file sharing might be disabled or not working. This condition prevents newer Macs from connecting to SMB network shares.
What to do
1) Go to Apple → System Settings → Sharing → File sharing → Info
2) Click on Options.
3) Check Share files and folders using SMB
4) Shut down your Mac, wait 10 seconds, then turn it back on.
That's it!