#418 Handle / Thread / USER Object leak


Running 0.7.3 version under Windows 2000 SP4. Using
Thunderbird as MUA. Two Yahoo accounts set up in
Thunderbird to retrieve mail (both Inbox and Bulk folders).

Each retrieval attempt causes the counts for Handles,
Threads, and USER Objects (as viewed in Task Manager)
to increase. These numbers continue to increase over
time, never decreasing until the program is closed.
This seems to signify a leak - and there are limited
numbers of each of these, so that over time, the
failure to release these objects will result in system

For example, on my system, Thunderbird is set to check
all accounts every 2 minutes (which, since it checks
them individually in sequence, and starts it's timer
after it checks the last one, means more like every 5
minutes). Leaving the system running for approximately
10 hours in this condition will exhaust one of those
three pools (I believe the USER Object pool exhausts
first), as indicated by the following error message
when attempting to open an application after the pool
has exhausted:

The application failed to initialize properly
(0xc0000142). Click on OK to terminate the application.

When checking this error message in the Microsoft
knowledge base, it appears to revolve around USER32.DLL
problems (which is what leads me to believe that the
USER Object pool is being exhausted first).

When watching the application in Task Manager after
it's been running for 3 - 4 hours, I noted the
following numbers (which changed each time one of the
Yahoo accounts was checked by Thunderbird through your

Handles Threads USER Objects
558 97 102
568 99 104
578 101 106
588 103 108
598 105 110
608 107 112
618 109 114

I hope this information is sufficient to help you track
down the problem. I would appreciate feedback on this
as you diagnose it.


  • Tracy

    Tracy - 2005-08-07

    Logged In: YES

    Additional information: This problem only appears to occur
    if the program is set to auto-start when Windows starts. If
    the program is started manually, the problem does not occur
    (even if the program was autostarted, then closed, then
    reopened manually).

  • Don Beusee

    Don Beusee - 2005-08-16

    Logged In: YES

    Do you have "download emails silently" checked? If not, try
    checking this to see if it stops the leaks. I assume there is no
    memory leak and only window objects?

  • Tracy

    Tracy - 2005-08-16

    Logged In: YES

    I do have "download emails silently" checked. I haven't
    tried unchecking it to see if that cures the problem, but
    the problem seems to be intermittant. I haven't been able to
    identify any specific root cause - the program can sometimes
    run for 2 days without any problem, then suddenly 6 hours
    later it's acting up. Other times, it starts from the
    instant the program is opened (it seems to be worse if the
    program is automatically started at login time, but it does
    still happen - albeit lower frequency of occurance - when
    run manually).

  • Don Beusee

    Don Beusee - 2005-08-17

    Logged In: YES

    Ok, then I don't think automatic startup is really the cause - just
    coincidence. Could it be more related to receiving attachments?
    Try 0.7.4 at http://dbeusee.home.comcast.net and let me know if
    mem usage also increases when this happens or not.
    Try also with the systray icon turned off. Restart it after you
    make this change.

  • Tracy

    Tracy - 2005-08-20

    Logged In: YES

    Been using 0.7.4 for about 3 days now, and haven't noticed
    any problems with it. I'm going to tenatively say that it's
    fixed in this version. If I notice the problem recurring,
    I'll open a new ticket.


  • Don Beusee

    Don Beusee - 2005-08-22

    Logged In: YES

    Cool. Closing.


Log in to post a comment.

Get latest updates about Open Source Projects, Conferences and News.

Sign up for the SourceForge newsletter:

No, thanks