I have encountered a strange behaviour of the windows shutdown / logoff
procedure when any of two specific applications is running at that time.
Although the application terminates, and the process disappears from the
process list, the shutdown will not continue. It will not even complete
terminating all the other programs, in some cases.
Also, the fact that I can then start new programs indicates that the
shutdown was truly aborted.

However, the programs do not use the AbortSystemShutdown API call or
anything like it! So for what reason could the shutdown still be aborted?

All suggestions welcome

Robert

Could they be returning 0 when processing the WM_QUERYENDSESSION message?
That might stop the shutdown if attempting to shut down Windows internally
calls ExitWindowsEx() with EWX_FORCEIFHUNG.


--
John Phillips
MVP - Windows SDK



"Robert" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> I have encountered a strange behaviour of the windows shutdown / logoff
> procedure when any of two specific applications is running at that time.
> Although the application terminates, and the process disappears from the
> process list, the shutdown will not continue. It will not even complete
> terminating all the other programs, in some cases.
> Also, the fact that I can then start new programs indicates that the
> shutdown was truly aborted.
>
> However, the programs do not use the AbortSystemShutdown API call or
> anything like it! So for what reason could the shutdown still be aborted?
>
> All suggestions welcome
>
> Robert
>
>
>

Not directly, but thanks: You gave me the right idea.
Since it's a VB application, there is no way to process WM_QUERYENDSESSION
directly, but I cancelled application termination first, in order to gain
time for a proper application shutdown. So the system thinks that the
application cannot terminate. Sigh...

Thanks again

Robert

"John Phillips" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> Could they be returning 0 when processing the WM_QUERYENDSESSION message?
> That might stop the shutdown if attempting to shut down Windows internally
> calls ExitWindowsEx() with EWX_FORCEIFHUNG.
>
>
> --
> John Phillips
> MVP - Windows SDK
>
>
>
> "Robert" <(E-Mail Removed)> wrote in message
> news:(E-Mail Removed)...
> > I have encountered a strange behaviour of the windows shutdown / logoff
> > procedure when any of two specific applications is running at that time.
> > Although the application terminates, and the process disappears from the
> > process list, the shutdown will not continue. It will not even complete
> > terminating all the other programs, in some cases.
> > Also, the fact that I can then start new programs indicates that the
> > shutdown was truly aborted.
> >
> > However, the programs do not use the AbortSystemShutdown API call or
> > anything like it! So for what reason could the shutdown still be
aborted?
> >
> > All suggestions welcome
> >
> > Robert
> >
> >
> >
>
>