Before I wiped my HD and reinstalled, I overlooked archiving Mailboxes from inside Mail - oops. Instead, I backed up everything in Mac Harddrive/Library and System, and also MyIdentity/Library and System files — almost 1 gig of stuff — thinking I could just pop those files back into their respective Library or System folders and be back as before. Included were 20 or so .mbox files in MyIdentity/Library/Mail/Mailboxes/1Folder-To-Restore.mbox. The mailboxes I want to restore were all On My Mac folders.
After re-install, I set up my Mail accounts again, and apparently retrieved most of the 5000+ messages from the past 3 years. But I'd like them sorted back into the 20 or so folders like before.
When trying to Import Mailboxes from the folder where these backed up .mboxes live, I get "Error. No valid mbox files were found."
Then, I put these backed-up .mbox files back in the Library folder where they were before re-install. The folders appear when re-launching Mail - but theyre empty...
OS 10.5.8 | Mail 3.6 (936)
In Mail, highlight one of those mailboxes, then in Mail's menu>Mailbox>Rebuild... any change?