Hello GigaG:
I am having an extremely similar problem. Here's the setup:
SBS 2003 R2 Prem w/ ISA 2004 SP3 as EDGE Firewall. The server has 2 NICs, one connected to the Internet, the other is VLANed into 4 adapters: VLAN 10: Wired Clients, VLAN 20: Wireless Clients, VLAN 30: VPN Clients, and VLAN 40: VoIP. All these VLANs are trunked (tagged) to my internal NIC and to a port on the switch--which is a memeber of all 4 VLANs. The VLANs each have some other ports assigned to them on the switch (DELL PowerEdge 5324, which is 802.1q compliant).
Like you, I can ping every single internal network, however, I am unable to get to anything on the Internet. Even weirder, I can get to 'companyweb' the default SBS sharepoint site, but I am unable to get to my WSS3 site at
located on the same server (so apparently, I can't resolve things in my own IIS server).
I've narrowed it down to these possibilities: 1) Firewall Access Policies (or Network objects or something) are not configured correctly; 2) System Policies on ISA are not configured correctly; 3) Something is not right with DNS, or 4) 2 & 3 together or all the above!
If anyone else could shed some light on this, it would be greatly appreciated!!
Craig E. Shea
IT Coordinator
TTEC