I am trying use a web service in a C# ASP.Net Web Application. The service is built in PHP and is located on some remote server not under my control so I cant modify it to add
"webservice" is a very generic term. Some types of webservice may implement a WSDL - but its not a requirement. IIRC a SOAP interface is required to provide a WSDL, and both nuSOAP and the PHP SOAP extension support WSDL. So it looks like the remote end hasn't been implemented properly.