I encountered several times that error. It is caused by a bug in your application. You made some sort of mistake in one of the source files, more precisely in ANOTHER FILE THAN THE FILE WHERE THE ERROR IS REPORTED. This was the explanation I found long time ago on the MSDN, I cannot point at this time where exactly. The explanation was proven correct every time I encountered that error. It's really painful to find such a bug but you have no option than to look for it.