Inherits a DI class

Hy,

When i Inherits a UserTablesMDClass like this :

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Public Class MySample

Inherits SAPbobsCOM.UserTablesMDClass

...

End Class

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i have an error message : my application is failed on the instruction :

Dim MyClassSample = New MySample

'ClassFactory don't provide the request class'

Have you an idea?

thanks