We are on Zimbra Network Edition 8.0.4x and every so often run into an issue on mailboxes where a few messages are marked for deletion at the same time and are sent to the trash. A short period of time later they re-appear in the inbox as if they were not deleted without any new messages to the conversation. We have not experienced this issue when using IMAP to access Zimbra but through the advanced web interface.
Is there something easy to check on this to see what could be the case. I looked at the mailbox.log file but it is a bit tough to follow a message via SSH and tail since we do have a decent volume of email.