Hi

I have fully working project in .net 3.5SP1, with EF 1 ORM.

I tried to upgrade to .net 4. No issue while upgrading...

Then i ran the project and got a NullExecptionError, with no stack trace... and no way to debug. Looking at the output windows i can read this:

System.Transactions Critical: 0 : <TraceRecord xmlns="http://schemas.microsoft.com/2004/10/E2ETraceEvent/TraceRecord" Severity="Critical"><TraceIdentifier>http://msdn.microsoft.com/TraceCodes/System/ActivityTracing/2004/07/Reliability/Exception/Unhandled</TraceIdentifier><Description>Unhandled exception</Description><AppDomain>OTCSouscriptions.vshost.exe</AppDomain><Exception><ExceptionType>System.NullReferenceException, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</ExceptionType><Message>Object reference not set to an instance of an object.</Message><StackTrace>   at System.Windows.StyleHelper.GetInstanceValue(UncommonField`1 dataField, DependencyObject container, FrameworkElement feChild, FrameworkContentElement fceChild, Int32 childIndex, DependencyProperty dp, Int32 i, EffectiveValueEntry&amp;amp; entry)
   at System.Windows.FrameworkTemplate.ReceivePropertySet(Object targetObject, XamlMember member, Object value, DependencyObject templatedParent)
   at System.Windows.FrameworkTemplate.&amp;lt;&amp;gt;c__DisplayClass6.&amp;lt;LoadOptimizedTemplateContent&amp;gt;b__4(Object sender, XamlSetValueEventArgs setArgs)
   at System.Xaml.XamlObjectWriter.OnSetValue(Object eventSender, XamlMember member, Object value)
   at System.Xaml.XamlObjectWriter.Logic_ApplyPropertyValue(ObjectWriterContext ctx, XamlMember prop, Object value, Boolean onParent)
   at System.Xaml.XamlObjectWriter.Logic_DoAssignmentToParentProperty(ObjectWriterContext ctx)
   at System.Xaml.XamlObjectWriter.Logic_AssignProvidedValue(ObjectWriterContext ctx)
   at System.Xaml.XamlObjectWriter.WriteEndObject()
   at System.Xaml.XamlWriter.WriteNode(XamlReader reader)
   at System.Windows.FrameworkTemplate.LoadTemplateXaml(XamlReader templateReader, XamlObjectWriter currentWriter)

Any help appreciated... Thanks John