Hi Mark. I have found that the best way to migrate that much data with minimal downtime is to make a local copy of the Domains folder and then FTP/transfer the local copy to the new server. You can take as long as you want to do that. Then on the day of the migration, put a backup MX in place to store all incoming email while your server is down, stop your SmarterMail services and do a differential transfer of only new mail since the first transfer. You can use FileZilla to do a proper differential. Once you are up and running on the new server, the Backup MX will deliver all held mail to your new server. Doing it this way causes no email loss and it's quite quick since you are only grabbing the differential. Please let me know if you have any further questions. My company has done dozens of SmarterMail migrations so I'm sure I can answer any questions you have. Thanks!
Linda Pagillo
Mail's Best Friend
Email: linda.pagillo@mailsbestfriend.com
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