Microsoft Outlook - know your .pst file

So, you've got your cell phone, your PDA and your laptop. You have your frequent flyer account numbers memorized, and you can grab a connection through O'Hare inside 10 minutes without breaking a sweat. You've got spare batteries, power converters and adapters for every configuration from Italy to Istanbul. You've got your contacts, e-mails, task list and calendar right at your fingertips at all times. You're a true 21st century road warrior, a digital marvel, proud, strong, organized, unstoppable. Right? Yeah, me too. Problem is, we're living on the edge of a knife and our road-show kingdom is actually a house of cards built on a less-than-perfect foundation - a little (or not-so-little) file called outlook.pst.

These instructions assume that you are using Outlook 2002 or 2003 in a stand-alone environment. If you are working in a corporate setting which utilizes Microsoft Exchange Server your data will be stored on a central server and these instructions will [may] not [exactly] apply. Also, if you have an earlier version of Outlook some of the file settings, locations and dialog boxes will be different. For information on earlier versions of Outlook look here.

OK, that may be a little over the top. Still, even if you only use Outlook from your home computer you've got the potential for trouble, because everything you use to store all of the information about the people you know, send and receive e-mails, schedule appointments, keep track of your daily tasks, and possibly more, is stored in a single file that can be, and at some point in time definitely will be, corrupted beyond repair. And when that happens you've got real trouble. Imagine loosing all of your contact information, all of your appointments, all of your e-mails, with no hope of getting them back. Ever. Getting a shiver down your back?

I manage the IT department for a mid-size global manufacturer based in the US, with a relatively small group of individuals that more-or-less live on the road. Of these 20 or so road warriors, about 2 or 3 of them will end up with corrupted Outlook files every year. That's a pretty high percentage. Granted, these folks use their equipment hard, and may not always be the best at routine computer maintenance. Still, it shows the potential for trouble, and when it happens it really can be a time-wasting hastle.

So here are a couple of tips that have helped me over the years, and should help you to keep Outlook happy and healthy.

  1. File maintenance - The first thing you need to do is to be aware of your Outlook source file, where it is and how big it is. Everything in Outlook is stored in a single file called Outlook.pst. Microsoft tells you that you can store up to 2 gb of data in your pst file, but I'm telling you it becomes wildly unstable way before that. If your pst file is larger than about 500 mb you're begging for trouble, and Outlook can get unruly when it's much smaller that that. It also needs to be compacted anytime your archive or delete any amount of data.

    So, the first thing you need to do is to look at (and inside) this file, so you know how big it is and what's using up all of the space. Start by right-clicking on your top-level folder in Outlook, probably called 'Personal Folders'. You should get a dialog box that looks like this:


    outlook survival 01


    Scroll to the bottom and select 'Properties for Personal Folders' to get another box that looks like this:


    outlook survival 03


    Now you want to go the bottom left and click on the button labeled 'Folder Size'. You'll get another dialog that will show you the size of the pst file, and the breakdown of all of the included subfolders along with their respective sizes:


    outlook survival 04


    The first thing to take note of is the overall size of the file, at the top labeled 'Total size (including subfolders)'. As you can see my file is in excess of 300mb, which is large but still workable. You should scroll down through the list to see which folders have the most data stored in them. This will come in handy when we archive some data later on. For now click on Close, then select 'Advanced' from the bottom right of the prior dialog box to get another one that looks like this:


    outlook survival 05


    There's two things to take note of here. The first is the 'Filename', which tells you where your Outlook.pst file is located. We'll need to know this later on when we back it up. The other thing to notice is the 'Compact Now' button. It is very important to compact your outlook.pst file any time after you have archived data or cleaned up your folders and deleted any amount of data. Beware, though, that compacting your data file can take many hours, although you can cancel out of it at any time. Cancel out of any open dialogs and we'll move to the next item.

  2. Archive your data - OK, so you've just discovered that your data file is huge, now what? The first thing we should talk about here is the AutoArchive settings. Microsoft knows that this file is going to get very large, and has a way for you to remove items out of it without actually deleting the data. They call it archiving, and the idea is to move older data into a backup pst file so that Outlook continues to behave. By default this is set to happen automatically every 14 days. To see how yours is configure go to Tools -> Options, select the Other tab, and click on the AutoArchive button to see a dialog that looks like this:

    outlook survival 06


    Hey, wait a second, someone has un-checked the box next to 'Run AutoArchive every ... days', how did that happen? Well, somewhere along the way I got sick of this AutoArchive box popping up every two weeks and told it not to remind me anymore. This is what happens most of the time, and where people get into trouble. The second most common thing everyone does is to just keep archiving into the same file until it gets so big it is no longer usable, at which point your old data is gone.

    Personally, I prefer to manually archive my data when I have the time, but you can certainly use AutoArchive if it works better for you. I usually suggest that you increase the time span to at least 30 days, or you'll just get sick of the reminder and cancel out of it. The other thing you really should do is to rotate your archive files so they don't get too large. I create new archive files every quarter, but you may only need to do it once or twice a year. You can always add items into your archive files, but you should keep them under 500 mb in size.

    OK, so let's archive some files. Go to the main menu and click on 'File -> Archive. You'll get a dialog box that looks like this:


    outlook survival 07


    A couple of things here. First of all, if you want to archive everything make sure you've selected the top level folder, usually 'Personal Folders', and make sure that the button 'Archive this folder and all subfolders' is selected. If you only want to archive a particular folder, say one that you saw from before that was very large, then just select that folder. Select a date, and any items that are older than this date will be put in the archive file. Last, you need to make sure you know where the file is going to end up. So click on the 'Browse...' button, then select or create a folder that is convenient for you. Outlook will remember this location and save to the same file in the same location next time you archive.


    outlook survival 08


    Click on OK, then click OK again to archive the files. This may take awhile, depending on how many items you have in Outlook.

    You will now see a folder in your Navigation pane called 'Archive folders', which will contain the items you just archived. You don't need to keep it there, you can right click on the folder and select 'Close archive folders'. And here's the biggest mistake everyone makes with archive files. When you want the data back do not import it. Instead, simply go to the main menu, select 'File -> Open -> Outlook Data File', then select the archived file you want to open. Simple as that.


    outlook survival 09


    Oh, now don't forget to compact your data file. Go back up to the instructions about and compact the file, but remember it might take awhile.

  3. Finally, back up your pst file - Every day, if you can. If you don't have a backup strategy yet you should get one. At the very least make of copy of the outlook.pst file (go above to review where it is located) and your archive files and burn them on a CD (assuming you have a CD burner). You can get an external hard drive for less than a lot of money if you don't. Get one, and use it. Just try to figure out how much information you're willing to loose, then you will know how often you need to back up the file

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