I have an aspx web pages which interacts with an asmx service.  The calls to
web service are done via Javascript.

The asmx service method has the following parameters:

public string RetrieveContact(string Id, int EntityTypeCode)

I am getting the following error when executing
oXmlHTTP.Send("id=" + sId + "&ObjectTypeCode=" + sObjectTypeCode);

which resolves into

oXmlHTTP.Send("id=7AA4FB86-24D6-DA11-B240-000F20F62526&ObjectTypeCode=1");

responseText "System.InvalidOperationException: Missing parameter:
EntityTypeCode.
  at
System.Web.Services.Protocols.ValueCollectionParameterReader.Read(NameValueCollection
collection)
  at System.Web.Services.Protocols.HtmlFormParameterReader.Read(HttpRequest
request)
  at System.Web.Services.Protocols.HttpServerProtocol.ReadParameters()
  at System.Web.Services.Protocols.WebServiceHandler.Invoke()
  at System.Web.Services.Protocols.WebServiceHandler.CoreProcessRequest()
" String

Would anyone know how to resolve this.

Thanks in advance