AutoCAD .NET :: Copying Data Drawing A To B

There is an error "Corrupted memory" when on several machines executing some code. I know the error is in the wblockcloneobjects from drawing A to drawing B.

The strange thing about this error is:

We have 6 computers with Civil and Autocad.

Some users have no errors at all.

Some people only errors when executing it in Civil, som only when executing it in Autocad, some have it in both.

This is almost a copy of the VB.NET sample from autodesk.

This is the code where it crashes:

Imports Autodesk.AutoCAD.ApplicationServicesImports Autodesk.AutoCAD.DatabaseServicesImports Autodesk.AutoCAD.Runtime
Public Class Class1
<CommandMethod("TEST", CommandFlags.Session)>
Public Sub CopyObjecten()
Dim oAppCivilDWT As String = "C:TemplatesCivil.dwt"
Dim oAppAutocadDWT As String = "C:TemplatesAutocad.dwt"
Dim oAppMechanicalDWT As String = "C:TemplatesMechanical.dwt"
RunMyCode

[Code]...

 All the modelpace objects needs to be copied to a template. (the full code does more stuff but this is the critical part)