There were some fixes posted before Lion that called for going to Library>mail>mailboxes>outbox.mbox file. Delete the mboxfile and that would work. Unfortunately the is no LIBRARY in the home folder to open so I have no idea what to do to fix the problem on a local level. We need some advice or a fix from Apple. They have always been very good about fixes and I'm sure someone is already working on it.
i found this solution to my 'i cant find my outbox' on an old forum at macroums and it worked for me
1. Close Mail Completely, right click Mail then Quit
2. go to ~/Library/Preferences,
if you cant find you Library directory under your user, open up Finder, then click 'Go' then 'Go To Folder' and put the folder in there and that wil take you straight there
3. open com.apple.mail.pllist with xcode or something similar
4. find this section:
5.Change DisplayInThreadedMode from NO to YES
6. save and reopen Mail
hope this works ok
Update on my issue. Somewhere between when I reported this and now, the Outbox appeared. I didn't have to do the edits described above. I cannot explain why one day it wasn't there and the next it was.
I used Thomas Suttles1 suggestion to remove the Outbox.mbox, but that lasted for 2 messages, and now the "new" Outbox shows messages waiting to be sent, but nothing is in there.
I did discover that messages now, though, ARE being sent. They are also being placed in the Sent folder, but the interface does not reflect those results - the barber pole "sending" indicator is still stuck in sending mode.
Issues discovered since last time: Deleted messages never get removed from the Inbox. If I delete a message, it disappears temporarily, but when I quit mail (usually force quit, because quitting hangs the app, even after waiting 24 hours) and launch mail again, the removed messages re-appear.
The app is generally sluggesh throughout the day as well.
But I can say that wiht 10.7.1, Safari is remarkably faster.
OK, so I was having the same problem and called Apple. They walked me through it and this is what you need to do.
The issue seems to be from IMAP accounts (mobile me, etc)
First delete or drag to Draft Folder all the messages stuck in your outbox, close mail.
Go to FINDER
OPEN Text Edit
Go to File (next to Apple logo)
Save As Dialog box opens, click on the triangle to display full FINDER options
CLICK AND HOLD COMMAND, SHIFT AND . (PERIOD) KEYS
While still in Text Edit with the FINDER SAVE AS window open, go to your user (little house with your name)
Then select your IMAP folder
Within that Folder you will have a sub folder that says CACHE (NOT .mbox.cache.plist)
Select that folder and drag to trash
Reopen MAIL and it should be fixed. It worked for me.
Jonathan, while I appreciate your response, your post doesn't make sense. Why do you open TextEdit to move something in the library to the trash? I tried to follow the steps, but 1) they don't work, so please check your work to see if you wrote them down correctly, (you can't drag something to the trash from a save dialog box) and 2) even if I manually go to the ~?=/Library/Mail/V2/my IMAP folder, I don't have a folder called CACHE. Even if I go there in Terminal (so I can see hidden files), there is nothing there called CACHE.
Oh dear. I tried this and it doesn't work with Mail 5.0 (1244.2/1244.3) -- particularly annoying since, while I'd quite like to have a permanently visible Outbox (reassurance, paranoia, whatever), it's actually become important. When messages fail to go (usually an SMTP authentication issue of some kind, which I often get on public wifis), Mail is no longer displaying the Outbox :-(
I know the mail hasn't gone, because I get one or two error messages and, when I do get it working again (usually be re-authenticating with a test message), I can see that the 'stuck' message is going too... but still no sign of the Outbox. Hopefully a fix... or even (finally) a Preferences option to just show the **** thing, will appear soon...?
I was thinking the same thing while the Apple Tech was walking me through it but it was the only way for me to get it fixed. The file (folder) says something like OFFLINE CACHE.
I tried to do it again and it shows me the files (though not the file Offlinecache that I deleted). Did you make sure to press and hold command+shift+PERIOD(.) keys? If you did press those keys together in the save as dialog box, you would see a file called .mboxCache.plist (not the file to delete and it's grayed out). You should see a blow folder icon containing Offline and Cache in its name. To Delete it, OPEN THE TRASH CAN and then drag that file to the trash. This fixed it for me.
This will not work from FINDER. It was done via Text Edit (following the steps).