Archive Outlook Safely, Effectively, Swiftly


Q I’ve been archiving my old Outlook files every few weeks since I loaded Outlook 2002, and now I can’t open the archive. Have I lost all those e-mails? Wasn’t I doing the right thing—keeping my old mails regularly archived—rather than leaving them in the Inbox?


A Well, let’s put it this way: You were doing the right thing—but doing it in the wrong way. Before I give you a short course in Outlook housekeeping essentials, I suggest you locate a competent computer technician to try to salvage your data. There is a Microsoft tool for recovering an Outlook.pst file that exceeds the maximum size for the application. You can download the free tool from It’s called the Oversized PST and OST crop tool. However, if your .pst file is larger than 2 gigabytes and you consider the data especially valuable, I would suggest you engage professional help rather than risk fumbling the task. In fact, even with professional help, the odds of a full recovery are not very good. In any case, you should make a backup copy of the .pst file before you or a professional try to recover it.


Prior to Office 2003, Outlook’s .pst files had a maximum size of 2 GB—that is, the file became unreadable if it exceeded 2 GB. Since then, Outlook was redesigned so the .pst files could support as much as 20 GB. But as a practical matter, it’s best not to let your .pst file get so big because such a fat file will make Outlook sluggish. Even worse, such large files are more vulnerable to corruption.


Recognize that Outlook’s .pst file stores a huge amount of complex information such as e-mails, calendar data, contacts, notes and to-do lists.


So, given the size restraints, how can you safely and conveniently archive its data? First of all, only save what you need. Regularly cull the trivia from your Inbox. And when you empty your Deleted Items box, don’t just press Delete, press Shift-Delete so the material is hard-deleted to save space. Depending on your volume of mail, consider doing this exercise once a week or at least once a month. After you’ve done some culling, defragment the .pst file by clicking on All Mail Folders, Personal Folders, Property for Personal Folders and finally on the Home tab and on Compact Now (see screenshot on right).


Now that you’ve done some preliminary sorting and compacting, I suggest one more housekeeping step before you archive: Back up your .pst and archive files.


The hardest part of the backup exercise can be finding the Outlook.pst file. Windows does not make it easy: The file is usually tucked under multiple layers of folders. You’ll usually find it under C:Name of your computer, AppData, Local, Microsoft, Outlook.


To make the task easier, I suggest using a backup tool that can customize files you want to back up. I use SyncBackSE; you can download a trial copy from


Now you’re ready to begin archiving. On your Outlook toolbar, click on Tools, Options, the Other tab and finally on AutoArchive (see screenshot below).


As you can see, AutoArchive (see screenshot below) gives you many options about when and what to archive. You can set it up to do the job automatically, or you can pick and choose when and what to archive.


And when the archive gets close to the maximum size, create other copies.



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