The invalidIUnknown managed debugging assistant (MDA) is activated when an invalid IUnknown pointer is passed to managed code from native code. The IUnknown fails to return success when queried for the IUnknown interface.
An unexpected error occurs when marshaling a COM interface pointer during argument marshaling.
An incorrect QueryInterface implementation on the COM interface passed to the CLR.
Correct the QueryInterface implementation.
This MDA has no effect on the CLR.
The description of the error.