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Remarks
Windows NT/2000 or later: The ExitWindows function asks applications if they want to terminate by sending WM_QUERYENDSESSION to the main window of all running applications.

Windows 95/98/Me: The ExitWindows function sends WM_QUERYENDSESSION to all applications except the one that called ExitWindows.

An application agrees to terminate by returning TRUE when it receives this message (or by allowing the DefWindowProc function to process the message). If any application returns FALSE when it receives the WM_QUERYENDSESSION message, the shutdown is canceled.

After the system processes the results of the WM_QUERYENDSESSION message, it sends the WM_ENDSESSION message with the wParam parameter set to TRUE if the system is shutting down and to FALSE if it is not.

The system does not allow new applications to start up during the shutdown process.

For an example, see Logging Off.
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Problema tuk e che nemojesh da si absolutno siguren dalil wse pak shutdown-a shte se izpylni ili shte byde cansel-iran ot nqkoj nesaglasen app (redaktor s otworen i nezapazen dokument sled dialog s potrebitelq) btw ti mojesh da si go sledish w log zaedno s metoda - heartbeat w edin fajl/registry key na 15 sec zapiswash tekushtata data i ako se razlichawa ot starata s da kajem poweche ot 25 sec - pishtish na umrqlo che "sarceto e spiralo" oswen ako ne si zapisal che e imalo shutdown attempt predi da kajem 2min kojto ochewidno e bil uspeshen makar che i na towa moje da mu se nameri cakata...

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