The most likelly cause is, the sim has closed abruptly, because you have likely have exhausted memory because of the combination of too many addons, to high setting, and a memory-hungry airplane you are probably using, so the abrupt crash of the sim has MADE Couatl.exe crashing, because Couatl couldn't receive the command from the sim to shut down, so it wasn't able to do all the proper cleanup it's normally supposed to do when the sim closes normally.
We tried to catch all the possible instances of this message, not because it's the cause of the problem, but because users might be mislead thinking Couatl.exe is the cause of it, when in fact it's the *victim* of the sim abrupt crash that would have happened anyway, but apparently we haven't found all of them.
Note that this would make any difference: the sim would have crashed anyway in that situation, just that you wouldn't seen this error, so you wouldn't be mislead thinking the crash was caused by Couatl.exe (which, by definition, CANNOT crash the sim, since it's an external .EXE, so it doesn't have any access to its memory).
I suggest to check the amount of free memory in a similar situation.-
