The following is a strategy you can use to start managing PSTs. First, discover all PST files known to Outlook mailboxes. If you know you have some large PST files out there and are worried about corruption, identify the largest files first. Record the PST file name, path and size, for later review.

Next, manage the content of PST files either on a scheduled, exception-driven, or one-time basis. Archive messages and attachments from PSTs according to a centrally controlled criteria. Place small message links in PSTs for easy user discovery and retrieval of archived messages and attachments, which also reduces the space requirements of PSTs. Compact PST files after messages are archived to recover unused disk space. And finally, index the archived PST data for fast search and retrieval. This provides your organization with some content control.

This process is a complex task. For situations where thousands of PSTs are involved, treat this as an ongoing process. Start with the priority files and work through the entire structure. You may want to look for an automated archiving product that will allow you to run these tasks on a scheduled, exception-driven or one-time basis. Beware of oversimplified solutions that don't allow for multiple criteria to run simultaneously; even a complex rule-set should be easy for the administrator to set up, use, and update.

Haber, at Fletcher Allen, started the medical center's archiving process by compressing PST files. "The databases are getting too big for reasonable recovery in a disaster situation. Before we started our archiving project, I thought it would be good to decrease the size of what they have," he says, noting that Fletcher Allen Health Care has more than 7,000 mailboxes. "We got 40 percent of the space back with a compression product."

Now he'll use an archiving product that includes a PST option to discover, index, and archive all PST files just like any other email message. In fact, he'll use it to archive more than 300GB of PST files. "For certain users, it'll appear as though they have unlimited space," says Haber. "No more 'reaching limits' messages."

Dave Hunt is the CEO at C2C Systems Inc., a leading provider of email lifecycle management solutions for Exchange. He can be reached at dave.hunt@c2c.com