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dyl666

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Outlook Web Access (OWA) - cannot access externally

Hi there

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/exchange 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.

Thanks!
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amaheshwari
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Can you see the requests even hitting the OWA server's IIS logs?
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dyl666

ASKER

No, I can't - I can see where the internal accesses are getting logged, and if I look back at the old log files I can see the last external entry in there, but nothing new is getting added now when I try from an external site. (I have identified the last external access time and can't think of anything that changed on or around that point in time.)
Try doing this:

Go under IIS, right click your server name, and under "Website Identification", it might be  showing your ip address as one of your internal NICS. you just select your external WAN nic, and everything will work.

Hi,
Check this
iis ...Server Name....Web sites...Default Websites ...Right click ....Website identification ...External wan nic.

Thanks
Ashish
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LeeDerbyshire
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Hi Lee,

it does seem to be doing exactly that - here is a line from the log file:

2006-05-08 13:13:41 216.9.241.76 - 10.10.5.1 80 GET /exchange/ - 404 Mozilla/4.0+(compatible;+MSIE+5.01;+Windows+NT+4.0)

(10.10.5.1 is the internal address of the proxy server.)
^^^ Which basically looks to me like it is locally looking for /exchange/ rather than forwarding the request on to the OWA server. This and similar lines are repeated for each attempted access. Interestingly, the log files only start directly after the access logs for OWA STOP denoting external access attempts - so, something obviously changed there but I am still at a bit of a loss as to what!
I would definitely re-check the ISA rules.  If you just go to http://servername (without the /exchange), which server does it reach then?
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ASKER

I'm not sure if you mean internally or externally - internally, it gets to an 'under construction' page on the OWA server. Externally, it gets the same 404 page that we get if we try with the /exchange on the end.

I will look into the ISA rules now - at first glance it looks like everything is right but I don't know much about them so will have to do a bit of reading I think...!
You will need to check the paths.  See if you have a rule that matches / (and everything underneath) to the OWA server, or if you have a specific rule for each path (including one for /Exchange).  The important thing to check is that an external path that includes /Exchange gets properly mapped to the same path at the OWA server.  Right now, it sounds like it is being mapped to the ISA server.
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ASKER

In the end I removed IIS completely. I couldn't figure out what it was doing there in the first place and guessed (correctly it seems) that it was just causing problems (it must have been installed but not 'activated' until a recent reboot).

I am giving Lee the points because his / her troubleshooting tips were helpful in tracing the problem and I was asking for general troubleshooting help with ISA / IIS as well as ideas for the specific issue.