Private Function validiereMemStream(ByVal mStream As MemoryStream) As String
 
        Dim ergebnis As String = ""
        Try
 
            strValidationErgebnis = ""
            Dim settings As XmlReaderSettings = New XmlReaderSettings
 
            settings.ValidationType = ValidationType.Schema
            settings.ValidationFlags = settings.ValidationFlags Or _
              XmlSchemaValidationFlags.ProcessSchemaLocation
            settings.ValidationFlags = settings.ValidationFlags Or _
            XmlSchemaValidationFlags.ReportValidationWarnings
 
            AddHandler settings.ValidationEventHandler, AddressOf _
              ValidationCallBack
            ' Create the XmlReader object.
            Dim reader As XmlReader = XmlReader.Create(mstream, settings)
 
            ' Parse the file. 
            While (reader.Read())
            End While
            ergebnis = strValidationErgebnis
            reader.Close()
        Catch ex As Exception
            Throw New ValidationException(ex.Message)
        Finally
            validiereMemStream = ergebnis
        End Try
    End Function

For Each Name As String In IO.Directory.GetFiles(strSchemas, "*.xsd")
                If InStr(Name, getSchemaname(mstream)) <> 0 Then
                    settings.Schemas.Add(getNamespace(mstream), Name)
                End If
                ' settings.Schemas.Add(Nothing, Name)
            Next