I'm in the process of deploying a WCF service application. The service works fine if it's running as its own site, but the intention is for the service to run as a virtual directory of the Default web site of the server. When I set the service up in this configuration, I get an odd problem. When the client tries to make a service call, it receives the HTML of the friendly service description, not SOAP. Naturally this generates a service error. The HTML appears to be identical to the service page that you see in a browser with an HTTP Get, but I'm only seeing the first 1024 bytes in the error message, so I may be missing something.
I've checked HttpHandlers and loaded assemblies, and as far as I can tell there's nothing unusual that is being inherited by the virtual directory. The default site has 3 ISAPI Filters installed including Outlook Web Access (yes, this server is running Exchange). I tried installing these filters in my test web site, but it still ran the service without problems. The problem only happens with the service is running as a virtual directory of another virtual directory within the default web site.
The server is Windows Small Bus Server 2003 SP 2 running IIS6.