kmail displays "No such file or directory" error message on startup with IMAP folder

[Stilor]

After I added an IMAP account to KMail, it started to display the "no such file or directory" message for one of the IMAP folders ("Other Users"). Right after I added that account, same error message was displayed for each of the IMAP folders, but they disappeared after the first run.

Package: kmail
Status: install ok installed
Priority: optional
Section: mail
Installed-Size: 9492
Maintainer: Kubuntu Developers <email address hidden>
Architecture: i386
Source: kdepim
Version: 4:4.3.1-0ubuntu1
Replaces: akonadi-kde (<< 4:4.1.3), kmail-kde4, kmailcvt (<< 4:3.90.0), kontact (<< 4:4.2.85)
Provides: imap-client, mail-reader
Depends: kdebase-runtime (>= 4:4.3.0), kdelibs5 (>= 4:4.3.1), kdepimlibs5 (>= 4:4.3.1), libc6 (>= 2.4), libgcc1 (>= 1:4.1.1), libindicate-qt0, libkdepim4 (= 4:4.3.1-0ubuntu1), libkleo4 (= 4:4.3.1-0ubuntu1), libkontactinterfaces4 (= 4:4.3.1-0ubuntu1), libkpgp4 (= 4:4.3.1-0ubuntu1), libksieve4 (= 4:4.3.1-0ubuntu1), libmimelib4 (= 4:4.3.1-0ubuntu1), libqt4-dbus (>= 4.5.1), libqt4-network (>= 4.5.1), libqt4-phonon (>= 4.5.1), libqt4-qt3support (>= 4.5.1), libqt4-xml (>= 4.5.1), libqtcore4 (>= 4.5.1), libqtgui4 (>= 4.5.1), libstdc++6 (>= 4.2.1), perl, kdepim-runtime
Recommends: gnupg, gnupg-agent, pinentry-qt4 | pinentry-qt | pinentry-x11
Suggests: kaddressbook, procmail, kleopatra, spamassassin | bogofilter | annoyance-filter | spambayes | bsfilter | crm114, clamav | f-prot-installer
Conflicts: kmail-kde4
Description: KDE Email client
 KMail is a fully-featured email client that fits nicely into the KDE
 desktop. It has features such as support for IMAP, POP3, multiple accounts,
 mail filtering and sorting, PGP/GnuPG privacy, and inline attachments.
 .
 This package is part of KDE, and a component of the KDE PIM module.
 See the 'kde' and 'kdepim' packages for more information.
Homepage: http://kontact.kde.org/kmail/
Original-Maintainer: Debian Qt/KDE Maintainers <email address hidden>