I just came across this article at WindowsMobile.com, and wanted to post it here for others:

• Start the Norton Personal Firewall application.
  
• Click the Personal Firewall icon in the main window, and click the Configure button in the right pane.
  
• A Personal Firewall Settings window will appear. Navigate to the Programs tab.
  
• Use the Programs tab to get to the Program Control window. Click the Add button to add an application.
  
• Navigate to the Microsoft ActiveSync installation folder (C:\Program Files\Microsoft ActiveSync\ if installed in C drive with default settings).

  Click the WCESMgr.exe, and then click Open.

  
• A Program Control window will appear. In the What do you want to do? drop-down list, select Permit.

  Click OK.

  
• Repeat steps 5 and 6 to add the following applications:
  Wcescomm.exe
  Rapimgr.exe
  CEAPPMGR.exe

  (C:\Program Files\Microsoft ActiveSync\ if installed in C drive with default settings)

  When all of these are added, the Program Control window should show these programs in the list at the bottom.

  Navigate to the Advanced tab.

  
• In the Advanced tab, click General…
  
• In the General Rules window, click Add.
  
• In the Add Rule Wizard, click the Permit option button, and press Next.
  
• In the following screen, click the Connections to and from other computers option button.

  Click Next.

  
• Leave the next screen as is.

  Click Next.

  
• In the next screen, be sure the TCP and UDP option button and the Only the types of communication or ports listed below option button are selected.

  Click Add.

  
• In the Specify Ports window, be sure the Individually specified ports and Remote option buttons are selected.

  In the port entry field below, enter "26675" as shown.

  Click OK.

  
• Click Next until you get to the Description screen. Choose a name for the rule, and click Next.
  
• You can choose to apply this rule to any location profile in the next screen.

  Click Next.

  
• Click Finish in the final screen.
  

I'd suggest that if you're still using Norton Personal Firewall 2004 that you need to pull your finger out and buy something less than 5 years old! 

P.s. Nice doc though Bill, and to be fair it's not much different in 2008 either! 

Dave Parker MVP:

buy something less than 5 years old

Good point! I didn't register that this app was that old! I'm not a Norton person - I've been using Kaspersky for a couple of years and have really been pleased with it.

Hopefully there are some steps in here that could help in various situations and with different security products, though...

 Certainly the port information will be useful for any firewall product.