Grazie ad entrambi,
dunque chiamando la pagina con ?wsdl mi visualizza xml :

<?xml version="1.0" encoding="UTF-8"?>

<wsdl:definitions xmlns:wsdl="http://schemas.xmlsoap.org/wsdl/" targetNamespace="http://tempuri.org/" xmlns:http="http://schemas.xmlsoap.org/wsdl/http/" xmlns:soap12="http://schemas.xmlsoap.org/wsdl/soap12/" xmlns:s="http://www.w3.org/2001/XMLSchema" xmlns:soap="http://schemas.xmlsoap.org/wsdl/soap/" xmlns:tns="http://tempuri.org/" xmlns:mime="http://schemas.xmlsoap.org/wsdl/mime/" xmlns:soapenc="http://schemas.xmlsoap.org/soap/encoding/" xmlns:tm="http://microsoft.com/wsdl/mime/textMatching/">




<wsdl:types>




<s:schema targetNamespace="http://tempuri.org/" elementFormDefault="qualified">




<s:element name="HelloWorld">


<s:complexType/>


</s:element>




<s:element name="HelloWorldResponse">




<s:complexType>




<s:sequence>


<s:element type="s:string" name="HelloWorldResult" maxOccurs="1" minOccurs="0"/>


</s:sequence>


</s:complexType>


</s:element>




---ECC ECC


</s:complexType>


</s:element>


</s:schema>


</wsdl:types>




<wsdl:message name="HelloWorldSoapIn">


<wsdlart name="parameters" element="tns:HelloWorld"/>


</wsdl:message>




<wsdl:message name="HelloWorldSoapOut">


<wsdlart name="parameters" element="tns:HelloWorldResponse"/>


</wsdl:message>










<wsdlortType name="WSSoap">




<wsdlperation name="HelloWorld">


<wsdl:input message="tns:HelloWorldSoapIn"/>


<wsdlutput message="tns:HelloWorldSoapOut"/>


</wsdlperation>






-<wsdl:binding type="tns:WSSoap" name="WSSoap12">


<soap12:binding transport="http://schemas.xmlsoap.org/soap/http"/>




-<wsdlperation name="HelloWorld">


<soap12peration style="document" soapAction="http://tempuri.org/HelloWorld"/>




-<wsdl:input>


<soap12:body use="literal"/>


</wsdl:input>




-<wsdlutput>


<soap12:body use="literal"/>


</wsdlutput>


</wsdlperation>








-<wsdlort name="WSSoap12" binding="tns:WSSoap12">


<soap12:address location="http://localhost:4587/WS.asmx"/>


</wsdlort>


</wsdl:service>


</wsdl:definitions>
Ho provato anche lanciando aspnet_regiis.exe -i ma niente.

Quello che funziona invece è da codice aspx:

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load Dim x As New WS
MsgBox(x.HelloWorld())



End Sub

e questo mi fa incavolare .... sto facendo intanto tutte le prove, inserirò nella pagina i link di jquery ecc in modo da forzarlo ad usare quelle da me indicate