I did some more tweaking, won't bore you with the details, but I have now got the ISA Server passing web requests through (I had to remove the entries from the paths tab and specify the path in the url) So I see the requests being passed when I watch the log, but the page comes up with: Error Code: 500 Internal Server Error. The data area passed to a system call is too small. (122) The last part of the message, according to what I have found on Google and MS could be because the url is too long, which would be weird since it is an IIS generated url to get to the owa start page, or it could be a whole bunch of other completely unrelated things, such as username and password using international characters, had me laughing anyways. Any thoughts on just why IIS would be chucking this error at me? Cheers Clayton Doige IT Project Manager CME Development Corporation T: 020 7430 5355 M: 07932 653787 E:clayton.doige@xxxxxxxxxxx W:www.cetv-net.com