We recently migrated to Office 365 from Exchange 2007 using a cutover migration. Users have been reporting that several emails are missing (ranging from 3 weeks before the cutover to 2 days before it). I haven't gotten rid of the old mail server yet in case something like this happened. Is there any way for me to be able to resync and have Office 365 check the mailboxes to bring up non-duplicated emails?
Thanks.