SMB: File and printer sharing ports should be open

Updated: February 2, 2011

Applies To: Windows Server 2008 R2

This topic is intended to address a specific issue identified by a Best Practices Analyzer scan. You should apply the information in this topic only to computers that have had the File Services Best Practices Analyzer run against them and are experiencing the issue addressed by this topic. For more information about best practices and scans, see Best Practices Analyzer.

Operating System

Windows Server 2008 R2


File Services






The firewall ports necessary for file and printer sharing are not open (ports 445 and 139).


Computers will not be able to access shared folders and other Server Message Block (SMB)-based network services on this server.


Enable File and Printer Sharing to communicate through the computer's firewall.

Membership in the Administrators group, or equivalent, is the minimum required to complete this procedure.

To open the firewall ports to enable file and printer sharing

  1. Open Control Panel, click System and Security, and then click Windows Firewall.

  2. In the left pane, click Advanced settings, and in the console tree, click Inbound Rules.

  3. Under Inbound Rules, locate the rules File and Printer Sharing (NB-Session-In) and File and Printer Sharing (SMB-In).

  4. For each rule, right-click the rule, and then click Enable Rule.

Additional references

Understanding Shared Folders and the Windows Firewall(