Hmm this is weird indeed. Have you tried to access the FPSE site from within the DMZ (that is, inside the ISA firewall scope) or is the ISA firewall on the same box as the webserver? Of course you can try to install the new release of the FPSE (included with SharePoint Team Services for W2K3 for example) but I'm afraid this won't help... (but you can always give it a try of course).
Bart De Smet [MVP]
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