I\'ve got multiple classes (including TPT) in my project. Each POCO has a BaseClass, which has a GUID (called GlobalKey) as primary ke
BaseClass
GUID
GlobalKey
I have also seen the same problem when the type of the field is off. Double check the type of the field Ex:
public string StateId {get;set;}
pointing to a domain object with int as the State.Id type. Make sure that your types are same.