DCOM ( Distributed Component Object Model) uses RPC ( Remote Procedure Call) dynamic port allocation to randomly selects port numbers above 1024. This makes it difficult to configure your firewall.

To confine dynamic port allocation to port 135, the RPC Endpoint Mapper, and to a range of dynamic ports you select:

01. Start / Programs / Administrative Tools / Component Services.

02. Expand the Component Services node.

03. Expand the Computers node.

04. Right-click My Computer and press Properties.

05. Select the Default Protocols tab.

06. Select Connection-oriented TCP/IP and press the Properties button.

07. Press the Add button.

08. Type a port range, like 5000-5020, into the Port range box, and press OK.

09. Insure that the Port range assignment and Default dynamic port allocation options are set to Internet range.

10. Press OK, OK, and OK.

11. Shutdown and restart your computer.