Soapaction HTTP Header
Problem
The soapaction HTTP header is a special HTTP header found in SOAP request messages that contains information about the web service being called. ASP. net web services require this header, and it must contain the namespace and (if applicable) the name of the method being called. if you are using. net Framework-based client, this header is automatically generated for you and you do not need to worry about it.
Apache SOAP web services, however, do not require any information from the soapaction header. an Apache Web service will be perfectly happy signing ing a message with an empty soapaction header (although the header itself must still be encoded in every SOAP message ). in the example earlier in this White Paper, we did not provide any soapaction in the Apache SOAP client we created; consequently, that clientWocould not workWith a. NET Framework-based Web service, even if the location and namespace of the Service were the same.
From: http://msdn2.microsoft.com/en-us/library/Aa478995.aspx
A theoretical basis found only after finding the crux of the problem
For specific errors, see the previous article.