When calling a method of my Web Service from an ASP.NET application, I receive this message:

The 'None:FaultCode' element is not declared. An error occurred at , (1, 1259). 

And, there is a big text:

[XmlSchemaException: The 'None:FaultCode' element is not declared. An error occurred at , (1, 1259).]
   System.Xml.Schema.Compiler.SendValidationEvent(XmlSchemaException e, XmlSeverityType severity) +94
   System.Xml.Schema.Compiler.CompileElement(XmlSchemaElement xe) +1692
   System.Xml.Schema.Compiler.CompileParticleElements(XmlSchemaComplexType complexType, XmlSchemaParticle particle) +54
   System.Xml.Schema.Compiler.CompileParticleElements(XmlSchemaComplexType complexType, XmlSchemaParticle particle) +371
   System.Xml.Schema.Compiler.CompileCompexTypeElements(XmlSchemaComplexType complexType) +102
   System.Xml.Schema.Compiler.CompileTo(SchemaInfo schemaInfo) +1396
   System.Xml.Schema.XmlSchema.Compile(XmlSchemaCollection collection, XmlNameTable nameTable, SchemaNames schemaNames, ValidationEventHandler validationEventHandler, String targetNamespace, SchemaInfo schemaInfo, Boolean compileContentModel, XmlResolver resolver) +187
   System.Xml.Schema.XmlSchema.Compile(ValidationEventHandler validationEventHandler, XmlResolver resolver) +211
   System.Data.DataSet.ReadXSDSchema(XmlReader reader, Boolean denyResolving) +51
   System.Data.DataSet.ReadXml(XmlReader reader, XmlReadMode mode, Boolean denyResolving) +1122
   System.Data.DataSet.ReadXmlSerializable(XmlReader reader) +9
   System.Data.DataSet.System.Xml.Serialization.IXmlSerializable.ReadXml(XmlReader reader) +55
   System.Xml.Serialization.XmlSerializationReader.ReadSerializable(IXmlSerializable serializable) +21
   Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationReader1.Read55_GetNewsDataSetResponse() +328

[InvalidOperationException: There is an error in XML document (1, 1753).]
   System.Xml.Serialization.XmlSerializer.Deserialize(XmlReader xmlReader, String encodingStyle) +415
   System.Xml.Serialization.XmlSerializer.Deserialize(XmlReader xmlReader) +7
   System.Web.Services.Protocols.SoapHttpClientProtocol.ReadResponse(SoapClientMessage message, WebResponse response, Stream responseStream, Boolean asyncCall) +1050
   System.Web.Services.Protocols.SoapHttpClientProtocol.Invoke(String methodName, Object[] parameters) +218
   MFUG.UserGroupMeetingTracker.UniversalThread.GetNewsDataSet(DateTime tdStartDate, DateTime tdEndDate, Int32 tnForum) in D:\iis\MFUG\Web References\UserGroupMeetingTracker\Reference.vb:276
   MFUG.News.Page_Load(Object sender, EventArgs e) in D:\iis\MFUG\News.aspx.vb:55
   System.Web.UI.Control.OnLoad(EventArgs e) +67
   System.Web.UI.Control.LoadRecursive() +35
   System.Web.UI.Page.ProcessRequestMain() +731

Basically, it chocks on the line GetNewsDataSet() from the WS or whatever is being returned. Anyone know how to understand this?