SBS 2003 SP1 Firewall Issues

Hey guys, nice to be a member now.

Just wondering if someone could help me get to the bottom of my strange problem.

I have some issues with my SBS network. I have a SBS 2003 SP1 Standard Edition server with 1 NIC and a client with XP pro (1 NIC). The network is set up on a domain and it working well and exchange server is handling the email. There is an ADSL Router that has a built in firewall, and both server and client connected directly to it.

The XP client has the Windows Firewall is using my domain settings and is working well (i know its not the best firewall, plan to replace it with something better), it also has Outlook 2003 installed.

However, I have a strange problem. When I enable the Firewall on the SBS, the XP client cannot connect to the exchange server, but there is still access to the My Documents folder (that is stored on the SBS. Additionally, when the SBS firewall is enabled i have problems with the Remote Workplace and I cannot log into the XP client, but I can log into the server with Remote Workplace. When I turn the SBS firewall off, Outlook connects to the Exchange server and I can access both client and server from Remote Workplace.

I do not think the problem lies on the router as I have forwarded everything that is needed.
I do not think the problem lies on the client as the firewall is always on and gets it settings from the domain.

I have also added the following parts of exchange to the exception list of the SBS firewall.

Microsoft Exchange MTA Stacks (Emsmta.exe)
Microsoft Exchange Information Store (Store.exe)
Microsoft Exchange System Attendant (Mad.exe)
Microsoft Exchange Site Replication Service (Srsmain.exe)

I have not found anything to assist me in the Administrator's manual book I bought

 

Access to file sharing uses a different set of ports than desktop sharing and remote workplace. I expect you will need to open up incoming traffic to ports 110 & 25 (for the e-mail) and 80 for the workplace. You should be able to restrict that access to only users on your local network by defining the rule to only allow incoming from your local subnet (for example 192.168.0.0 if your server address is 192.168.0.1, or 10.0.0.0 if your server is 10.0.0.1).

I don't use the workplace system so am not sure of which ports it will use. I expect it is 80, but it might be others too.

 

The ports open are 25, 110 (for email) and 80 and 4125 (for workplace).

Still the same problem.