This exception signals an attempt to access an AppDomain that has been unloaded by AppDomain.Unload( ).

public class AppDomainUnloadedException : SystemException {
// Public Constructors
   public AppDomainUnloadedException( );
   public AppDomainUnloadedException(string message);
   public AppDomainUnloadedException(string message, Exception innerException);
// Protected Constructors
   protected AppDomainUnloadedException(System.Runtime.Serialization.SerializationInfo info, 
        System.Runtime.Serialization.StreamingContext context);
}

Hierarchy

Object Exception(System.Runtime.Serialization.ISerializable) SystemException AppDomainUnloadedException