PST / NST files: Concerns and implications

By Datalink
7/11/2011

We've all received messages from our IT departments stating that our mailboxes are approaching the company-defined quotas, and that we must “clean” our mailboxes to reduce their size. So what do we do? We can selectively delete messages that we “think” we don’t need, then of course Murphy’s Law kicks in and we need to refer to a message that we have deleted. Now what? Our only other option is to “archive” the mailboxes ourselves. Both Microsoft Exchange and Lotus Domino provide built-in, easy-to-use utilities that allow us to reduce the size of our mailboxes by moving messages into an archive file. In Exchange, this is a .PST file, and in Domino, it's an .NSF file.

So what really happens when we archive? Messages in your mailbox that meet the criteria you entered (i.e., all messages older than two years) are removed from the mail server and placed into the .PST or .NSF file. While this reduces the size of your mail file and satisfies your IT department, it also creates a number of problems. If you created the archive on your personal computer, IT no longer has the ability to protect the data. If you created the archive on a shared drive, IT may back up the data, but when you leave the office and work remotely, you no longer have access to those archived messages, because they are not on the mail server or your PC.

From a discovery perspective, messages moved into .PST or .NSF files cannot be discovered, which can result in sanctions and/or fines if your legal counsel cannot produce messages when requested in litigation. From a sheer volume perspective, think of how many copies of the same message are stored in multiple .PST or .NSF files, and how much expensive storage is wasted to store multiple copies of the same message (i.e., everyone saves the message from HR announcing benefits and enrollment, which typically has large attachments).

Many companies are assessing and implementing archiving solutions to alleviate all of these issues. With archiving solutions:

  • Configuring automatic archiving policies enables our mailboxes to remain within established quotas.
  • All items in the archive are protected by IT backup policies.
  • All items in the archive are single-instance stored or deduplicated, so we only store one copy of a message, regardless of how many copies there are.
  • All messages in the archive are discoverable.
  • Any existing .PST or .NSF files can be migrated into the archive.

Check my previous blog post for more info on this topic. Or, feel free to comment and I’ll weigh in.