Troubleshooting .NET “Fatal Execution Engine Error”

Question

Summary:

I periodically get a .NET Fatal Execution Engine Error on an application which I cannot seem to debug. The dialog that comes up only offers

Answer 1

A presentation that might be a nice tutorial on where to start with this kind of issue is this: Hardcore production debugging in .NET by Ingo Rammer.

I do a bit a of C++/CLI coding, and heap corruption doesn't usually result in this error; usually heap corruption either causes a data corruption and a subsequent normal exception or a memory protection error - which probably doesn't mean anything.

In addition to trying .net 4.0 (which loads unmanaged code differently) you should compare x86 and x64 editions of the CLR - if possible - the x64 version has a larger address space and thus completely different malloc (+fragmentation) behavior and so you just might get lucky and have a different (more debuggable) error there (if it occurs at all).

Also, have you turned on unmanaged code debugging in the debugger (a project option), when you run with visual studio on? And do you have Managed Debug Assistants on?