To reproduce, switch of the unread column, then create a new subfolder. I created a new subfolder of sent-mail, and it now shows "sent-mail (0 + -1)"
*** Bug 233411 has been marked as a duplicate of this bug. ***
*** Bug 233412 has been marked as a duplicate of this bug. ***
This is maybe a model, view, or delegate bug, so adding Steve to CC list.
SVN commit 1127232 by vkrause: Ignore invalid CollectionStatistics objects when calculating the recursive counts. BUG: 233410 M +1 -1 collectionstatisticsdelegate.cpp WebSVN link: http://websvn.kde.org/?view=rev&revision=1127232