I've been developing a WCF web service using .NET 3.5 with IIS7 and it works perfectly on my local computer. I tried publishing it to a server running IIS 5.1 and even though I can view the WSDL in my browser, the client application doesn't seem to be connecting to it correctly. I launched a packet sniffing app (Charles Proxy) and the response for the first message comes back to the client empty (0 bytes). Every message after the first one times out.

The WCF service is part of a larger application that uses ASP .NET 3.5. That application has been working fine on IIS 5.1 for awhile now so I think it's something specific to WCF. I also tried throwing an exception in the SVC file to see if it made it that far and the exception never got thrown so I have a feeling it's something more low level that's not working.

Any thoughts? Is there anything I need to install on the IIS5 server? If so how am I still able to view the WSDL in my browser?