I get this strange error 'System.Windows.Data.ListCollectionView' is not marked as serializable
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I have a method which clones a class. This class contain subclasses and properties etc.
Is it causing due to ICollectionView-Property?
How to detect where the problem is? I mean which property or class is not marked serialized or something? Very confusing...

Error:
Type 'System.Windows.Data.ListCollectionView' in Assembly 'PresentationFramework, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' is not marked as serializable.