Best solution for complex issue - migrating large mail archive to Ubuntu box
 

Here is the scenario:
I have a large email archive that I use every now and then for reference and search. Currently it's only available from one workstation and I'd like to have it accessible from any IMAP client on any machine. I already have all of the Postfix/Dovecot connection issues taken care of.

Where I need help is how to approach getting all of the mail which is currently in Thunderbird's mbox format on a single windows machine - onto my net-accessible Ubuntu box in Unix format. Somewhere out there has to be a better solution than trying to forward all of the emails to the new mail account on the server.

If there isn't a better solution - are there any concerns about trying to send many thousands of mails across the internal network? I'm just looking for the best, most logical way to approach the issue.

Thanks... Ubuntu 10.04 - Postfix/Dovecot - SSL/TLS IMAP connection.

There is probably a variety of ways to accomplish this, but the easiest is likely to be to set up the IMAP account in Thunderbird on the Windows machine and copy the email archive over.

Are you saying that if I were to create the IMAP account on the windows box and connect to the mail account on the server - somehow the mail client on the the Windows box would populate the folder structure and copy the contents over to the Linux box?

Thunderbird supports multiple mail accounts at the same time. If you create an IMAP account pointing to your new server archive, you can drag and drop the entire existing local mail archive to the IMAP account which will upload all your mail to the server. Depending on your Thunderbird version and/or extensions installed, you may have to drag and drop the folders individually.

Once all the mail has been uploaded to the IMAP server, as soon as you connect to it from the Linux box Thunderbird will populate the account there.

Ok. Seems like I understand.

1) Create an IMAP account on the Win box which connects to the Linux machine.
2) Drag the folders (one by one if need be) from the existing archive account into the new IMAP account.
3) This will essentially load the mails onto the server?

Yes, set up the IMAP account to connect to your dovecot server (which will be your new central email repository). Dragging the folders will move the mail to the dovecot server (typically stored as a maildir). If you want to just copy them it might be a little more tedious as Thunderbird's folder management is pretty clunky: I would probably just make a backup of your Thunderbird profile and use the backup profile to move the mail over (this would probably be a good idea regardless) which then could simply be deleted when you're done.

Once the mail is copied, any email client connecting to the dovecot server will download any mail it doesn't already have (including the original windows machine).

That's exactly what I wanted.. Logic.. Thank you very much. Makes perfect sense. I'll report back how it goes.

So far - it seems like Thunderbird doesn't want to move folders around - but has no problem at all copying from one folder to another. So all you have to do is recreate the folder structure and then copy the mails from one to the next. That seems to be working.

Now I've discovered that if you create the new folder on the new server archive and then drag the folder over from the old account - it will bring the folder and its sub-folders over without complaint. That is the ticket..