Here's the problem -- at some point in the past couple of months, Yahoo decided to delete about 18 months worth of my email. This apparently happened sometime around the 7th of May (since that's the earliest date in my inbox). Fortunately, I am diligent about backups and have a complete copy of my Thunderbird profile from before that time.

My question is, how to restore email from my backup. I tried shutting down Thunderbird and copying INBOX (and INBOX.msf & INBOX.mozmsgs) from the backup into my current profile. But seeing as this is an IMAP account, as soon as I started up Thunderbird it synchronized with the server, noted that these files did not exist on the server and promptly deleted them from the local Thunderbird file. I'm assuming that if I copy the complete profile instead of just the mail files the same thing will happen. I assume I need to get them back onto the IMAP server. Ideas?