This problem has seemingly come from out of the blue - or, if something has caused it, it hasn't been documented at all (I've been away on holiday and noticed it when I came back. The individual who covered for me tells me that nothing changed).
In a nutshell, I can access OWA by typing servername/exchange into a web browser internally, but when I try http://webmail.domainname.com/exchange
(which has worked flawlessly in the past) into a browser on a computer outside our building I now get a 404 error.
I have tracked the 404 error down to coming from our proxy server (I edit the .html page manually on the proxy server with some identifying text and this text appears in my browser). On the proxy server, in ISA Management, there is a rule setup to forward all traffic from the destination webmail.domainname.com/exc
hange to the mail server. This rule hasn't changed. The proxy server can ping the mail server just fine and all other connectivity is working without a hitch. I don't think it's a firewall issue as if this were the case I wouldn't expect to see a 404 from our server.
We *have* had some strange traffic problems recently where people browsing web pages are also getting 404s but I believe this is unrelated.
Please let me know if you have any ideas! I have searched for help in the MS knowledge base (and of course here) but there doesn't seem to be any relevant documentation for this exact issue and my knowledge of ISA / IIS is quite lacking so am not too sure how to proceed.
We are running Exchange 2000, and Windows 2000 Server.