What to do about Outlook's huge PST Con't

To create a new .pst, select File, New, Outlook Data File..., then select "Office Outlook Personal Folders File (.pst)", and OK. In the next dialog box specify the location and name of your new .pst. I tend to place my archive .pst files in a common mail directory on another machine on my network, but keeping it along side your existing personal folders is also common. Pick something that reflects how you'll organize your email, and press OK.

In the next dialog, specify the display name (I usually just use the file's name). Leave the other settings as they are for now, and press OK.Once you've created your new .pst, it will show up at the bottom of your email or file folders list. You can expand it, create sub folders in it, and drag and drop messages from your old .pst into your new one.

Your new pst will automatically show up each time you open Outlook. You can explicitly close it, if you like, (Right click on it, and select "Close") which will speed up Outlook's start time somewhat. To open it again later, select File->Open->Outlook Data File....As it turns out it is possible to create a PST that's larger than 2 gigabytes. Unfortunately that's where the trouble starts.The problem manifests when you start Outlook, and it complains about the PST, typically instructing you to use the Inbox Repair Tool.
Step one, then is to do exactly that. You can read more about the Inbox Repair Tool, called scanpst in http://support.microsoft.com/?kbid=197316

If scanpst fails, and the PST file is at or over 2 gigabytes (2,147,483,648 bytes) in size, then you have a problem; you are going to lose some email.Microsoft has made available an Oversized PST and OST Crop Tool (http://support.microsoft.com/?kbid=296088)

The crop tool does just that ... it crops, or cuts, the size of the PST file by a specified amount to make it smaller. Small enough to run scanpst on, which can recover the contents of the PST. Any messages in the portion of the PST that was cut is lost.

The lesson here, of course, is to keep an eye on the size of your PST. While it would be nice if Outlook actually prevented PSTs from growing beyond the limits Outlook can handle, it may not, and obviously it can result in lost messages. Make sure to have a decent backup strategy, and keep an eye on your PST size