Ok, I've been pulling my hair out about this, and I'm hoping someone out there can help. I've noticed that if I create an ASP.NET project in VS2008, then add a WCF webservice file, I then can't get any subsequently-added ASMX web services to work correctly from the client. Please try to replicate this:
1) Create a new ASP.NET project.
2) Add an AJAX WCF service file to that project.
3) Add a reference to default.aspx via ScriptManager to the svc file. The intellisense works great and any client calls via javascript to that WCF work correctly.
4) I then add a Web Service to that project. I add a reference to that ASMX file to ScriptManager. Javascript intellisense fails to recognize any methods in that ASMX file, and any calls made to it via javascript fail.
This weirdness also works in reverse: if you add the web service first, then add a WCF service, any calls made ...
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