Mail that has been reported as lost has generally been found as:
1. Local mail that may not have been uploaded to Connect (Office 365 or Google Apps) sometime in the last year and still exists on the user’s computer.
2. Mail that is in Connect, but not where the user expects (in Google Apps, it can be found most easily in the "All Mail" category using Google Web Access).
3. Messages that would not migrate, usually due to Google’s file type restrictions. Users were notified in advance of these limitations by their unit contact and allowed a minimum of 60 days after migration to retrieve these messages from Office365, if needed.