Ports 137-139 are for NetBios/Name resolution. Without it you will have to access machines by IP address opposed to NetBIOS name. Example \\192.168.1.100\share_name opposed to \\my_file_server\share_name. So port 445 is sufficient if you can work with IP addresses only.

CIFS is the primary protocol used by Windows systems for file sharing. CIFS uses UDP ports 137 and 138, and TCP ports 139 and 445. Your storage system sends and receives data on these ports while providing CIFS service. When left open, these ports are susceptible to a variety of traditional attacks – like brute-force password guessing – but also to more modern ransomware attacks (such as WannaCry). In these cases, we recommend that the client either (1) disable Windows File Sharing on this server or (2) set up firewall rules to make the ports inaccessible To make file and printer sharing work in Windows, you must open the associated system service port in Personal Firewall.To learn how to open system service ports, read Set up a new system service port. Server Message Block provides file sharing, network browsing, printing services, and interprocess communication over a network. The SMB protocol relies on lower-level protocols for transport. The Microsoft SMB protocol was often used with NetBIOS over TCP/IP (NBT) over UDP, using port numbers 137 and 138, and TCP port numbers 137 and 139. NBT

Hello all, How to forward windows file sharing ports in DSL modem. I forwarded ports 22, 23, 80 and 3389, they are working fine, I am able to access them from public network.

Nov 09, 2019 · They are nothing but Communication protocols that provide a secure way of accessing shared data via printers, ports, and more. Microsoft’s SMB Protocol follows NetBT and this article provides detailed steps of enabling SMB 1.0/CIFS File sharing support on Windows 10 operating system. Jump to: Enable SMB 1.0/CIFS File sharing support Windows 10 Jul 20, 2020 · The best way to do that would be using the built-in Windows Firewall (or any other firewall) to block the TCP ports used by SMB-in and/or SMB-out connections. For those who don’t know, SMB is the acronym for Server Message Block , a sharing protocol for files and printers used by Windows operating systems since the early ’90s.

Allows inbound file and printer sharing. To do this, Windows Firewall opens UDP ports 137 and 138, and TCP ports 139 and 445. If you enable this policy setting, Windows Firewall opens these ports so that this computer can receive print jobs and requests for access to shared files.

To open the firewall ports to enable file and printer sharing. Open Control Panel, click System and Security, and then click Windows Firewall. In the left pane, click Advanced settings, and in the console tree, click Inbound Rules. Under Inbound Rules, locate the rules File and Printer Sharing (NB-Session-In) and File and Printer Sharing (SMB-In).