If it wasn’t for the fact that Thunderbird felt so sluggish in OS X, I’d ditch Mail.app (hereby known as Mail) right now. I just spent hours and I mean hours trying to figure out what was wrong with the “Sent Messages” mailbox I store on my imap server. Messages for the last 7 days were not appearing and to top it off, messages from 2002 were appearing either as duplicates or as something other than what the subject line said. Obviously it was having some serious issues reading the file and I thought things were bad, bad, bad I tell you. Then I realized how if I coped “Sent Messages” to a new file called “Sent2″ and read it in Mail, all my messages appeared properly. To top it all off, Thunderbird was reading everything just fine! Why must Mail be so finicky?
The end problem was that my mailbox file (which I keep in mbox format) was a little too unorganized for Mail to properly read. Normal people probably will never have this issue but because I’ve migrated from multiple mail accounts over the years, messages from 2003 come before messages from 2001 and then 2006 is just clumped together here and there. It’s a mess but technically, it should not matter because a mail application just reads these items while sorting is done locally by the applicaiton — not on the server. Guess not in Mail’s case.
Fix: I loaded Thunderbird, moved all “Sent Messages” to a new folder called “Temp” then moved them back to “Sent Messages” in hopes that it would slightly reorder the contents of the file. It did, and now Mail is happy and I can continue using Mail. Sheesh.