.Mac Mail sends old sent mail arbitrarily

Question

For some reason when I look at my Sent mail folder it shows old mail sent today. In other words if I look at my send mail folder and all the mail Sent Date mail says Today there's 1 or 2 pieces of mail that also says Today but I orginally sent it in May. If you look at the header of the mail itself there is no sent date. I don't know if these are being resent or its just a bug in the app. and shows it in my mail folder.
Any ideas??
Thanks,
Andrew

Answer 1

You’re welcome.
It does certainly matter how the messages were sent because AFAIK .Mac webmail doesn’t set the Date header on the copy of messages sent that way that it puts in Sent. Neither Mail nor any other mail client can reliably determine the sent date of a message if that header is missing...
Messages sent with Mail have an X-Mailer header that says so when received. That header isn’t present in the copy of the message that Mail puts in Sent, but it can probably still be determined whether a message was sent with Mail or with webmail by looking at the full headers of the message (which you can see doing View > Message > Long Headers).
That said, it isn’t clear what your problem really is with the information you’ve provided. It could also be that you’re experiencing some index corruption and Mail is indeed resending some messages on its own. If you suspect that’s the case, you may proceed as follows.
Verify/repair the startup disk (not just permissions), as described here:
The Repair functions of Disk Utility: what's it all about?
After having fixed all the filesystem issues, if any, and ensuring that there’s enough space available on the startup disk (a few GB, plus the space needed to make a backup copy of the Mail folder), try this:
1. Quit Mail if it’s running.
2. In the Finder, go to ~/Library/Mail/. Make a backup copy of this folder, just in case something goes wrong, e.g. by dragging it to the Desktop while holding the Option (Alt) key down. This is where all your mail is locally stored.
3. Locate Envelope Index and move it to the Trash. If you see any other “Envelope Index”-named file there, delete it as well.
4. Move any “IMAP-”, “Mac-”, or “Exchange-” account folders to the Trash. Note that you can do this with IMAP-type accounts because they store mail on the server and Mail can easily re-create them. DON’T trash any “POP-” account folders, as that would cause all the mail stored there to be lost.
5. Open Mail. It will tell you that your mail needs to be “imported”. Click Continue and Mail will proceed to re-create Envelope Index — Mail says it’s “importing”, but it just re-creates the index if the mailboxes are already in Mail 2.x format.
6. As a side effect of having removed the IMAP account folders, those accounts may be in an “offline” state now. Do Mailbox > Go Online to bring them back online.
Note: For those not familiarized with the ~/ notation, it refers to the user’s home folder. That is, ~/Library is the Library folder within the user’s home folder, i.e. /Users/username/Library.