When this happens, the following is printed over and over to stdout:

kmail: WARNING: [void KMFolderImap::setImapPath(const QString&)] ignoring empty path
ASSERT: debug output not ended with \n
[
0: /opt/kde3/lib/libkdecore.so.4(_Z11kdBacktracei+0x41) [0x4069e571]
1: /opt/kde3/lib/libkdecore.so.4(_Z11kdBacktracev+0x2b) [0x4069e90b]
2: /opt/kde3/lib/libkdecore.so.4(_ZN10kdbgstreamD1Ev+0x88) [0x406aaf88]
3: /opt/kde3/lib/libkmailprivate.so(_ZN12KMFolderImap11setImapPathERK7QString+0x6e) [0x40222b5e]
4: /opt/kde3/lib/libkmailprivate.so(_ZN12KMFolderImap10readConfigEv+0x355) [0x40365265]
5: /opt/kde3/lib/libkmailprivate.so(_ZN8KMFolderC1EP11KMFolderDirRK7QString12KMFolderTypebb+0x4cb) [0x40396f1b]
6: /opt/kde3/lib/libkmailprivate.so(_ZN11KMFolderDir12createFolderERK7QStringb12KMFolderType+0x6e) [0x40399f0e]
7: /opt/kde3/lib/libkmailprivate.so(_ZN12KMFolderImap14slotListResultERK11QStringListS2_S2_S2_RKN5KMail15ImapAccountBase7jobDataE+0x2ea) [0x403bb2ea]
8: /opt/kde3/lib/libkmailprivate.so(_ZN12KMFolderImap18slotCheckNamespaceERK11QStringListS2_S2_S2_RKN5KMail15ImapAccountBase7jobDataE+0x40c) [0x403bc03c]
9: /opt/kde3/lib/libkmailprivate.so(_ZN12KMFolderImap9qt_invokeEiP8QUObject+0x203) [0x40484a43]
10: /usr/lib/qt3/lib/libqt-mt.so.3(_ZN7QObject15activate_signalEP15QConnectionListP8QUObject+0x17e) [0x40a6b98e]
11: /opt/kde3/lib/libkmailprivate.so(_ZN5KMail7ListJob15receivedFoldersERK11QStringListS3_S3_S3_RKNS_15ImapAccountBase7jobDataE+0x117) [0x402d8447]
12: /opt/kde3/lib/libkmailprivate.so(_ZN5KMail7ListJob14slotListResultEPN3KIO3JobE+0x1cf) [0x402d86df]
13: /opt/kde3/lib/libkmailprivate.so(_ZN5KMail7ListJob9qt_invokeEiP8QUObject+0x77) [0x402d8777]
14: /usr/lib/qt3/lib/libqt-mt.so.3(_ZN7QObject15activate_signalEP15QConnectionListP8QUObject+0x17e) [0x40a6b98e]
15: /opt/kde3/lib/libkio.so.4(_ZN3KIO3Job6resultEPS0_+0x92) [0x41b4a922]
16: /opt/kde3/lib/libkio.so.4(_ZN3KIO3Job10emitResultEv+0x7c) [0x41baa84c]
17: /opt/kde3/lib/libkio.so.4(_ZN3KIO9SimpleJob12slotFinishedEv+0x4c) [0x41bb200c]
18: /opt/kde3/lib/libkio.so.4(_ZN3KIO7ListJob12slotFinishedEv+0x6e) [0x41bb23be]
19: /opt/kde3/lib/libkio.so.4(_ZN3KIO7ListJob9qt_invokeEiP8QUObject+0xfb) [0x41ba54eb]
20: /usr/lib/qt3/lib/libqt-mt.so.3(_ZN7QObject15activate_signalEP15QConnectionListP8QUObject+0x17e) [0x40a6b98e]
21: /usr/lib/qt3/lib/libqt-mt.so.3(_ZN7QObject15activate_signalEi+0xc6) [0x40a6c136]
22: /opt/kde3/lib/libkio.so.4(_ZN3KIO14SlaveInterface8finishedEv+0x2c) [0x41b500ec]
23: /opt/kde3/lib/libkio.so.4(_ZN3KIO14SlaveInterface8dispatchEiRK9QMemArrayIcE+0x8b8) [0x41b84bb8]
24: /opt/kde3/lib/libkio.so.4(_ZN3KIO14SlaveInterface8dispatchEv+0x63) [0x41b5f8b3]
25: /opt/kde3/lib/libkio.so.4(_ZN3KIO5Slave8gotInputEv+0x2b) [0x41b60c5b]
26: /opt/kde3/lib/libkio.so.4(_ZN3KIO5Slave9qt_invokeEiP8QUObject+0x9a) [0x41b8801a]
27: /usr/lib/qt3/lib/libqt-mt.so.3(_ZN7QObject15activate_signalEP15QConnectionListP8QUObject+0x17e) [0x40a6b98e]
28: /usr/lib/qt3/lib/libqt-mt.so.3(_ZN7QObject15activate_signalEii+0xed) [0x40a6bfbd]
29: /usr/lib/qt3/lib/libqt-mt.so.3(_ZN15QSocketNotifier9activatedEi+0x30) [0x40dbfb90]
30: /usr/lib/qt3/lib/libqt-mt.so.3(_ZN15QSocketNotifier5eventEP6QEvent+0x50) [0x40a8b400]
31: /usr/lib/qt3/lib/libqt-mt.so.3(_ZN12QApplication14internalNotifyEP7QObjectP6QEvent+0x8f) [0x40a08c4f]
32: /usr/lib/qt3/lib/libqt-mt.so.3(_ZN12QApplication6notifyEP7QObjectP6QEvent+0x83) [0x40a0a813]
33: /opt/kde3/lib/libkdecore.so.4(_ZN12KApplication6notifyEP7QObjectP6QEvent+0x221) [0x40719a11]
34: /usr/lib/qt3/lib/libqt-mt.so.3(_ZN10QEventLoop23activateSocketNotifiersEv+0x116) [0x409fcdf6]
35: /usr/lib/qt3/lib/libqt-mt.so.3(_ZN10QEventLoop13processEventsEj+0x702) [0x409b6062]
36: /usr/lib/qt3/lib/libqt-mt.so.3(_ZN10QEventLoop9enterLoopEv+0xa1) [0x40a20be1]
37: /usr/lib/qt3/lib/libqt-mt.so.3(_ZN10QEventLoop4execEv+0x26) [0x40a20a26]
38: /usr/lib/qt3/lib/libqt-mt.so.3(_ZN12QApplication4execEv+0x1f) [0x40a0a6df]
39: kmail(_ZN12QApplication16x11ClientMessageEP7QWidgetP7_XEventb+0x2da) [0x804a696]
40: /lib/tls/libc.so.6(__libc_start_main+0xd0) [0x40fc5e80]
41: kmail(_ZN7QObject16checkConnectArgsEPKcPKS_S1_+0x35) [0x804a401]
]

Not a crash.

Do you have multiple versions of KDE installed on your system? Looks like kmail might be picking up an old version of kdelibs/qt .

Just tried the new Beta2.

Kmail no longer freezes permanently, but it still quite often temporarily climbs to 90% CPU usage (especially on startup, and when changing folders). In general it feels much less snappy than it used to in 3.4

Just tried RC1.

Kmail is still slower than it used to be until 3.4.x (especially right after startup).

However, there seems to be some improvement since Beta2 ;-)

does the problem persist in 3.5.0 or 3.5.1? If not, you should probably close this bug as WORKSFORME. If there are other problems (slowness, etc), put them in a separate bug report.

The freeze and CPU usage still happen. Moreover, at kmail startup, the following message is printed over and over again to stderr:

kmail: WARNING: [void KMFolderImap::setImapPath(const QString&)] ignoring empty path

> kmail: WARNING: [void KMFolderImap::setImapPath(const QString&)] ignoring
> empty path _______________________________________________


Your account seems to be corrupted if several folders do not have an imap 
path. Does it help to recreate it?

I wiped all my kmail config, and tried to re-configure my account.

However, in the current kmail config dialogs there seems to be no place where to configure the mail directory...

And yes, while kmail tried to index all my files in my home-directory as if they were mail folders, it was dogslow as hell, while the UI was basically frozen (no refresh, no reaction to any mouse or keyboard events)

Time for kill -9.

Well, no big loss, I had switched to Thunderbird anyways a couple of months ago.

The configuration file for KMail is: ~/.kde/share/config/kmailrc and the data directory is: ~/.kde/share/apps/kmail . Could you try moving this file and directory away and starting KMail?

Does this problem persist with the latest KMail and a completely clean config (create a new user, and try with that user)?

Feedback timeout, but please reopen if the problem persists (see comment 10)

Sorry for the slow response. But due to this issue and numerous other kmail issues, I switched to Thunderbird a while ago.

However, just for testing I tried kmail again, from a clean config (wiping my old kde/share/apps/kmail kde/share/config/kmail.eventsrc kde/share/config/kmailrc, the problem could still be reproduced.

Immediately after connecting to server, kmail became slow (> 80% CPU consumed), and totally unresponsive (pthread issue?). Moreover, it was scanning non-mail related files just as if they were folders. Ok, back to Thunderbird. These stability and performance issues in kmail are a *major* drawback for me. Thunderbird, on the other hand, works just fine.

Alain, do you have time to investigate this further? If so, we can probably think of some things to try, otherwise it's probably best to close the report.

I do have a small amount of time, so let's give it a try.

OK, some things that might be useful if you have the time:

* If you can, get the latest 3.5 branch version from SVN. If not, 3.5.6 will be out fairly shortly, so you might prefer to wait to try that.

* Just to be 100% sure that the problem isn't due to some old config files, create a new user, and run KMail with that user.

* If KMail freezes, kill it with "kill -SEGV <pid-of-kmail>". That should get you a backtrace dialog, from which you can paste the backtrace here. If there's debug output on the console, that might be useful too

*** Bug 141165 has been marked as a duplicate of this bug. ***

Please reopen, if you can provide the needed information (tests with a newer version of KMail), thanks.