We have an existing installation of GFI MailArchiver 5 with several databases of archives (perhaps 100-150GB). The goal is to export each user's archived e-mail and then import it into Exchange 2010 SP1 Personal Archives. GFI has a tool to do this, but it's very rudimentary and has severe, frankly unworkable, limitations. It only allows me to query based on the e-mail headers. Due to the fact that we have multiple aliases that may show in multiple headers (To:, Cc:), not to mention the fact that this won't cover a user's membership in a distribution group at a given point in time, this tool will not suffice.
Another option is for me extract the e-mails from the GFI databases without using the tool, but this would require me to write my own tool to reconstruct them and I really would rather not go down that path.
I feel very stuck on this issue. Has anyone here done a similar migration? How can this best be handled?