Hi folks. I've been working with Microsoft support on this but thought I would post anyway. We're doing a migration to Exchange 2007 from SunOne (IMAP) 5.x. The tool does work (with individual username and password combinations... we haven't been able to get the admin password to work in this case) and the "story" is a lot better than a tool like Transend where you have to create a profile for each target user (thus you have to know the destination username and password too).
But we do see dropped mail. I've worked with Erik A. briefly and I'm working with MS on it. So far the dropped mail includes mail missing properties like the subject line, and mail that's very large, like 50MB mails. Unfortunately our customer has no mail send limits as a research institution. That said, we have set all Exchange settings for maximum message size to unlimited.
At the end of the day the workaround may be to have a good backup before we do this, and if the client screams, restore the email. It would just be better to be able to say "this tool will not drop any emails, regardless of how big they are or how blank certain properties may be in the source system".
Any thoughts or ideas from the community appreciated.