One of the great features introduced with Office 365 (and Exchange 2010) was the Personal Archive or Archive Mailbox. With organizations moving away from PST files to improve security and control over sensitive data, a server-based archive is essential. The fact that one is now included in Exchange is a huge benefit for many organizations.
For organizations transitioning to the Microsoft platform from other mail systems, the Personal Archive is a great target for data previously stored in local archives. However, many organizations wonder about the best method for converting data and populating the Personal Archives. Many consolidate the historical data to each user's primary mailbox and allow the archive policies to populate the Personal Archive in advance of the primary migration. On the surface, this seems like a logical approach, but organizations soon discover a major problem.
The policies for the Personal Archive (and AutoArchive in Outlook) are based on the creation date of each item rather than send date, receive date, etc. Unfortunately, the creation date is an Exchange system date. Even if your chosen solution populates the original creation date during the migration to Office 365, these values will be overwritten with the current date and time. As a result, migrated content will not be archived based on the original creation date from the source platform or even the date it was received. Instead, migrated data will not begin flowing into the Personal Archive until the new creation date (i.e. the migration date) meets the archive policy.
I have spoken with several organizations that discovered this fact after migrating a significant number of users. Unfortunately, this results in excess data in the primary mailbox and quota issues for many of the users. Ouch!
So, how does one avoid this situation? Fortunately, for organizations migrating to Exchange from other mail platforms, Quest's GroupWise migration and Notes migration solutions support the Personal Archive as a direct migration target. As a result, GroupWise archives, local NSF files from Notes, and even historical data from the source mailbox can be migrated directly to the Personal Archive in Office 365 (or Exchange 2010). The more recent data can be migrated directly to the primary mailbox.
Microsoft has discussed the possibility of expanding the dates available to use in setting archive policies, but I have not heard a firm commitment on the specific release. Until this option becomes available, using the Personal Archive target in Quest's migration solutions can streamline the transition process for your organization.