Common .pst File Questions

This week, I address some of the inevitable questions that Outlook users eventually ask about Personal Folders (.pst) files. Personal Folders questions arise every day—sometimes dozens of times each day—in Microsoft's Outlook newsgroups. Even in Microsoft Exchange Server environments, where people use .pst files for archiving and, sometimes, to keep data out of their mailboxes, such questions are common. (See also, "Dealing with .pst Files" and "PST Auditing and Reporting").

If you don't have an Exchange Server mailbox, all your Outlook data resides in a .pst file. Someday, you might want to move that file to another folder on your computer. To locate your main .pst file, right-click the Outlook Today folder and choose Properties. (If the .pst file you want to move isn't your main data store, right-click the top level of the hierarchy instead of Outlook Today.) In the Properties dialog box, click the Advanced button to see the filename and path for your .pst file. You can't change the path in that dialog box, but knowing the path gives you enough information to locate and move the .pst file manually. Close Outlook; you might have to wait a couple minutes to make sure that it shuts down completely. Next, go to the location that the Properties dialog box specified and move the .pst file to a new location on your computer. When you restart Outlook, the application will prompt you for the file's new location.

If you don't see the .pst file in the folder that Outlook Today's Properties dialog box pointed to, you're probably using Windows XP or Windows 2000, which consider .pst files to be system files and hide them by default. Open Windows Explorer, and choose Tools, Folder Options. On the View tab, select "Show hidden files and folders." After you close the dialog box, you should be able to see the .pst file in the folder. If you know where the .pst file resides, you can move it, back it up, or copy it to a new machine when you upgrade. However, before you perform any of these operations, you must shut down Outlook.

If you've been archiving to the same archive.pst file for a long time (e.g., since Outlook 97 came out), you might want to search your computer for all .pst files and check their sizes. If a .pst file exceeds 2GB, Outlook can't open it. The pst2gb.exe tool, which you can get from Microsoft Product Support Services (PSS), can help you recover most of your data, but you probably won't get it all back. Try to keep any .pst files well under that 2GB limit. To maintain reasonably sized .pst files, delete messages you don't need to keep, empty the Deleted Items folder regularly or automatically, and occasionally compact the .pst file to remove the empty space that remains after you delete items. To compact the .pst file, right-click your folder's top level (Outlook Today if it's your main data store), click Advanced, and click Compact Now. Unfortunately, you can't schedule the compact function or launch it from a command line.

If you have an Exchange Server mailbox, you might have configured Outlook to archive data to a .pst file automatically, or you might have moved data to a .pst file for safekeeping after completing a project. Perhaps you've even burned a .pst file to a CD-R—although if you have, be aware that Outlook can't open the .pst file from the disc. Outlook requires write access to any .pst file. Therefore, to open the file, you must copy it from the CD-R to your hard disk, open the copied file's properties, and clear the read-only setting.

Must you import a .pst file to access your archived Outlook data? Importing is a spectacularly bad idea because you must archive everything all over again to get the old data out of your main Outlook folders. Instead, click File, Open, Personal Folders File (in Outlook 2002, Outlook Data File), then click View, Folder List to see the entire folder hierarchy from the .pst archive.

What other .pst file questions are plaguing you? Let me know, and I'll try to find some answers.