MY domain data email is on a 2008R2 server . I cannot install the latest SmarterMail server on 2008R2, so must upgrade the device to 2012R2+. . I cannot upgrade for another week, but email is down and cannot endure that much more downtime . I can use a VPS with later OS for SmarterMail installation and reference the email files on the 2008R2. I cannot find a definitive answer as to whether that would work, though seems like should be possible.