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We have a big application, and to ensure that our customers don't have the message "XXX has stopped working", we added some handler(in which we logs some errors and some other stuff).

It is working fine, we already solved a lot of issues like this(by analysis the logs after the exception arrived). But recently, someone managed to get the "XXX has stopped working" message anyway.

Currently we have the following implementation:

Application.ThreadException += HandleUnhandleException;
Application.SetUnhandledExceptionMode(UnhandledExceptionMode.CatchException);
AppDomain.CurrentDomain.UnhandledException += HandleUnhandleException;

Which is done at the very beginning of our application.

My question: Do you see any case where I can have an exception that display the mentionned popup("XXX has stopped working") without coming in this handler?

J4N
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  • Do you have any unmanaged code? AFAIK this can cause such errors. – Dawnkeeper Jan 28 '16 at 14:33
  • @Dawnkeeper: Some yes, but very small code(like some copy between some array), which has been highly tested(and should be always the same – J4N Jan 28 '16 at 14:39
  • You might want to look at [This Question](http://stackoverflow.com/questions/150544/can-you-catch-a-native-exception-in-c-sharp-code) – Dawnkeeper Jan 28 '16 at 20:25
  • @Dawnkeeper I'm not sure to understand the relation with the native exception? This would mean that I got a `Win32Exception`, which is not the case – J4N Jan 29 '16 at 08:32

1 Answers1

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What do you mean by "the start of our application"?

I have found that on rare occaision, AppDomain and Application handlers can still fail even in the Main function. One workaround is to put them in a static constructor of the same class as the entry point, as this preempts even Main.

Some exceptions cannot be caught, such as the most obvious Stack Overflow, which will prevent catching and logging from happening. This can happen most often if your program enters an infinite recursive loop.

See the question on List of exceptions that CAN'T be caught in .NET as it may shed some more light on that.

Community
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David
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    It's in the `Main`. But the message has been displayed hours after the mainform has been displayed, this code has already been executed, 200% positive – J4N Jan 28 '16 at 14:34
  • In the link, only the `StackOverflowException` cannot be caught – J4N Jan 28 '16 at 14:37
  • The answer also goes over how thread aborts get re-raised, has a link to corrupt states, and has several other answers, all of which could elad to this behaviour since it's _acting_ like an uncatchable error – David Jan 28 '16 at 14:39
  • But I guess this would not prevent the error from being logged, no? – J4N Jan 28 '16 at 14:40
  • A stack overflow certainly would; I'll update my asnwer – David Jan 28 '16 at 14:41