If a program crashes for no apparant reason - how to tell what caused it?

[VaxoP]

My program is very hard to debug as it uses 2000 winsock threads running simultaneously exchanging data all the time. Recently though it has been crashing for no reason - no error message or anything.. it just goes poof. Is there any way to tell what caused the error, does windows keep a log file or anything? Adding statements to log every detail in the app would not work as the CPU use would just be too high..

[zeezee]

does windows keep a log file or anything?

Yes. Check the System Event Log

in XP, go to
Control Panel -> Administrative Tools -> Event Viewer.
Try the Category Application.

Might have something there.

[VaxoP]

thanks
i checked though but theres nothing there related to my app

[zeezee]

Have you got all the updates and service Packs installed?
And in the event log, may be your app name is not there, but something related to it (a dll or service used by your app) could be there.
I know it wont be easy to check for that.
Does it have proper Error Trapping?