OK, Evil might be a bit of an exaggeration, but its not far off in my book. I dont know how many times I've seen people save precious emails to their local hard drives only to have the drive crash and not be able to recover them. From an administrators point of view I certainly understand how this happens. Some administrators say, "Im running out of space on my SAN" or simply, "Im trying to get people to use less storage space" (the most common reason I've come upon for IT teaching people how to setup PST Archiving.) PST Archiving allows you to back up Outlook data to a .pst file, which is stored locally on your computer rather than on the e-mail server.
Each .pst file contains all of your Outlook folders, including the Inbox, Calendar, and Contacts. You can have a single .pst file (usually called Personal Folders in your Folder List), but you can also have an additional .pst file that you use for archiving. Using the Personal Folders Backup tool, you can back up any or all of these .pst files.
Sadly, there hasn't been a good way to archive mail until Exchange 2010 came along, and to be more precise, not until Exchange 2010 Service Pack 1. Exchange 2010 introduced an archive mailbox for a user that you could use policies against in order to move mail from the main mailbox to the archive mailbox. This meant you could say, "anything older than 90 days gets moved into the Archive mailbox." This mailbox could be mapped in your Outlook and when you use search it will return you answers from you standard mailbox and the Archive mailbox as well. The only downside with this is that the Archive mailbox had to remain in the database with the users actual mailbox. Although this was a great proof of concept it was little more than that with this limitation.
Then Microsoft released SP1 for Exchange 2010 and the sky cracked open and angelic music sprang forth, at least thats the way I remember it. The reason for all the rejoicing was that now we can place the Archive mailboxes in their own database and that database can even live on slower storage. This means we can have a tiered storage approach to the archiving mailbox and limit the risk of mail loss. More good news is that you can manage this with policies in Exchange AND you can continue to uses quotas as well.
Email archiving is only one of the many great things to come out of Exchange 2010. Database Availability Groups, Online Mailbox moves, Rich OWA features and Role based administration are a few of my favorites. If you're already on Exchange 2010 now is a good time to start using these new features. If you're not on Exchange 2010 yet, what are you waiting for?
Hope to see you back here soon!