

Thunderbird may have run into a problem downloading a "bad" (malformed) message.You can also close Thunderbird and manually delete them from your profile folder they will be rebuilt when Thunderbird starts. To rebuild a folder listing right-click on that folder in the folder pane, select Properties, and choose "Rebuild Folder" from the General Information tab. It's possible that the ".msf" files (so called index files used to cache the folder listing) are corrupted.If you read the message using one email client that message will appear as read in the other email clients. IMAP accounts support multiple email clients reading messages in the same mailbox.For POP accounts, check to see if you have Thunderbird set up to automatically download new messages.See Disappearing mail for other ways you might overlook a message. Make sure the drop down View menu is set to "View all messages.If you received an alert saying that new messages have arrived but there are no new messages in your Inbox folder and you didn't get an error message, use this check list. This article was written for Thunderbird but also applies to Mozilla Suite / SeaMonkey (though some menu sequences may differ).
