Checking whether the client can communicate

If your Windows client is not communicating with the SMB server, make sure that the SMB traffic can communicate over the following TCP/IP ports, depending on which method you are using:

137-139: NetBIOS
445: TCP/IP direct option

It is possible that the SMB traffic is being restricted from getting to the SMB server; for example, a firewall may be in place. Contact your network or system administrator to verify that this traffic is permitted.