How to undo Mail Rebuild.

Question

O.K. I did it one more time by blindly following leads to solve a problem with my mail
When starting Mail I -was able to- read the messages in my inbox. After awhile they disappear giving me a msg where normally the email body is read: "The message from Wayne Mallett <[email protected]> concerning “Mail Subject” has not been downloaded from the server. You need to take this account online in order to download it."
So I looked online here :
http://forums.macosxhints.com/showthread.php?s=&threadid=29787
and followed the following link from one of the postings:
http://docs.info.apple.com/article.html?artnum=25812
And did a mail rebuild .
All the files in my in-box disappreared.
I quit and restarted mail and it did someindexing and total files in inbox now is zero ( + a couple of new emails), and thousands of mails in my inbox seem to be gone.
Is there any way that I can undo this rebuild and get the files in the inbox back?
Someone please help!

Answer 1

As you can see, letting a mailbox grow indefinitely is a really bad idea. If you’re just starting to experience the problem, doing what the Overstuffed mailbox is unexpectedly empty article suggests might work. If you’ve let the problem to become worse over time, however, it may be too late to solve it as described in the article, but you may still be able to fix it as follows:
1. Quit Mail if it’s running.
2. Assuming this is a POP account, in the Finder go to ~/Library/Mail/POP-username@mailserver/.
3. Locate INBOX.mbox and move it to the Desktop.
4. Open Mail. A new empty INBOX.mbox will automatically be created within the account folder, and this will allow you to continue using Mail normally while trying to solve the problem.
Although INBOX.mbox appears to be a file, it’s actually a special kind of folder (a package) that contains several files. Ctrl-click on INBOX.mbox and choose Show Package Contents from the contextual menu to see the files it contains. Of these files, mbox is the most important and is where all your messages are stored. What’s the size of that file? Depending on its size, you may or may not be able to directly import it back into Mail in the next step.
An Incoming_Mail file may also be present, in which case it might contain messages that Mail couldn’t transfer to mbox. Incoming_Mail is also a standard mbox file like mbox proper, just named differently, and can be imported back into Mail in the same way.
5. In Mail, do File > Import Mailboxes and follow the instructions to import the INBOX.mbox that’s on the Desktop. I’m not sure what the import options available in Mail 1.x are, but you should choose Other / Standard mbox or something like that, so that Mail looks at the mbox file only (and Incoming_Mail, if present) and ignores the other files in the package.
If Mail doesn’t let you select INBOX.mbox in step 5 because it’s a package instead of a plain folder, rename INBOX.mbox to just INBOX (i.e. remove the .mbox suffix) so that it becomes a normal folder, and try again. You cannot do this directly in the Finder because removing a suffix by normal means causes the Finder to hide the suffix instead of renaming the file. To remove the suffix from the name, you must do File > Get Info (⌘I) on the file and change the name there.
If the mbox file is too big for Mail to handle it, however, you’ll have to break it into smaller pieces. You can do that with an MBOX Breaker Script available at Allan Sampson’s website, or with Emailchemy. The former will ignore the Incoming_Mail file that I mentioned previously, but you may try importing that file directly if it’s not too big or just ignore it if all your messages are in mbox. Also, if you removed the .mbox suffix from the name of the mailbox, you may need to add it back again for the script to recognize it.
If all is well and you don’t miss anything, the files on the Desktop can be deleted, although you may want to keep them for a while, just in case.
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.