When SQL Server 2005 or SQL Server 2008 Developer Edition, Express Edition, or Evaluation Edition is running on Windows XP Professional or Windows 7 and Developers want to connect to this instance from another computer, they must open a communication port in the firewall. The default instance of the Database Engine listens on port 1433; therefore, Developers do not have to configure a fixed port. However, named instances including SQL Server 2005 or SQL Server 2008 Express Edition listen on dynamic ports. Before Developers can open a port in the firewall, they must first configure the Database Engine to listen on a specific port; otherwise, the Database Engine might listen on a different port each time it is started. Developer should follow the next steps to configure SQL Server:

1. In SQL Server Configuration Manager, expand SQL Server 2005 Network Configuration or SQL Server 2008 Network Configuration, and then click on the server instance they want to configure.

2. In the right pane, double-click TCP/IP.

3. In the TCP/IP Properties dialog box, click the IP Addresses tab.

4. In the TCP Port box of the IPAll section, type an available port number. For example they can use 1700.

5. Click OK to close the dialog box, and click OK to the warning that the service must be restarted.

6. In the left pane, click SQL Server 2005 Services/SQL Server 2008 Services.

7. In the right pane, right-click the instance of SQL Server, and then click Restart. When the Database Engine restarts, it will listen on port 1700.