Why Experts Think PST=BAD
The following section is reprinted by permission of the author (Ed Crowley). Items 11, 12 and 13 are courtesy of Stephen Gutknecht. This list is based on input from the many PST=BAD proselytisers in the Exchange Discussion List and personal experience.
PST=BAD #1. They're fragile, especially as they get big. They get corrupted too easily.
PST=BAD #2. You have to run the Inbox Repair Tool on them way too often.
PST=BAD #3. Your users don't back them up if they’re on their own PCs.
PST=BAD #4. Your users don't compact them. They just get bigger and bigger.
PST=BAD #5. Your users forget their PST passwords. Even though there are unsupported tools to crack them, it can take a significant amount of time to do so.
PST=BAD #6. You lose single instance storage (SIS).
PST=BAD #7. Messages take up more space in a PST than in an Exchange store.
PST=BAD #8. It's simply nuts to store PSTs on a network drive. They just end up taking up more space. Is disk space on your file server cheaper than disk space on your Exchange server?
PST=BAD #9. One might think that it will be easier to restore a single mailbox by using server-based PSTs, but corruptions, problems in successfully completing backups if a user is still accessing a PST file, and the ability for users to inadvertently delete PST files….
PST=BAD #10. For road warriors, OSTs are a much superior storage technique, especially with the improvements made with Outlook 98. They allow untethered computing at a higher level than with PSTs, plus with the added security of a backed-up information store on the server.
PST=BAD #11. A PST can be opened by only one machine at a time. This precludes a manager and assistant from working from the same PST simultaneously, and precludes team access.
PST=BAD #12. You cannot use Outlook Web Access to read your downloaded messages.
PST=BAD #13. Future applications, such as unified messaging, will be poorly implemented when using PSTs. Groupware applications that work with the mailbox probably won't work at all.
PST=BAD #14. PST files are not secure. Anyone with access to the PST file can open it using the right tools.
PST=BAD #15. You cannot clean up PST files after virus infestations.