I've just been hit by this bug I think. I'm getting the "Detected a corrupt mbox file or an invalid 'From' header" error, and my mailbox seems completely screwed. A lot of my mails seem to be duplicated. Mail from years ago seem to be unread, and all my labels and follow up flags and follow up dates have completely disappeared. On 3000+ e-mails!
I've just been hit by this bug I think. I'm getting the "Detected a corrupt mbox file or an invalid 'From' header" error, and my mailbox seems completely screwed. A lot of my mails seem to be duplicated. Mail from years ago seem to be unread, and all my labels and follow up flags and follow up dates have completely disappeared. On 3000+ e-mails!