That may be one cause, but it certainly isn't the only one, as I experienced this using disconnected IMAP a few times. I never used any anti-spam or anti-virus features.
-- [Data Loss] KMail mysteriously changes messages to "No Subject", "Unknown" sender https://bugs.launchpad.net/bugs/50039 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
