Version: 1.11.1 (using 4.2.1 (KDE 4.2.1), Kubuntu packages) Compiler: cc OS: Linux (i686) release 2.6.27-11-generic I have a filter that moves messages from my inbox to another folder. Sometimes I see kmail move the new message into this folder and a blue "(1)" unread indicator is shown beside it. This then disappears after about 1 second and the message is nowhere to be found. Quiting kmail and restarting shows the message again so the message is not actually lost or deleted but it is annoying to have to quite and restart kmail constantly just to be able to read new messages.
Thank you for taking the time to file a bug report. KMail2 was released in 2011, and the entire code base went through significant changes. We are currently in the process of porting to Qt5 and KF5. It is unlikely that these bugs are still valid in KMail2. We welcome you to try out KMail 2 with the KDE 4.14 release and give your feedback.