Reference to a tool within an extension no longer working ...

Hello

We have recently moved our computers from Windows NT to Windows 7, and at the same time we've upgraded from ArcGIS 10.1 to 10.2.

I have an ArcGIS extension created in Visual Basic 2010, which had been running well in the previous set up. I have moved things over onto my new computer in this new environment, and now something is not working.

I have on some of my forms a click event which access one of the tools elsewhere in the same extension. When the click event is accessed now a unhandled exception error comes up "Object reference not set to an instance of an object".

I've obviously missed, or forgotten doing something which I had previously done. Could anyone help with what that might be. Here is the offending click event ...

Private Sub cmdSelect1_Click(ByVal eventSender As System.Object, ByVal eventArgs As System.EventArgs) Handles cmdSelect1.Click

Dim pUID As ESRI.ArcGIS.esriSystem.UID = New ESRI.ArcGIS.esriSystem.UID
Dim pCommandItem As ESRI.ArcGIS.Framework.ICommandItem = Nothing

Dim Application As ESRI.ArcGIS.Framework.IApplication = m_pApp

pUID.Value = "{" & SelectFPoint.ClassId & "}"

pCommandItem = Application.Document.CommandBars.Find(pUID, False, False)
pCommandItem.Execute()

End Sub