Working with Outlook data files

Applies to
Microsoft Office Outlook® 2003

This is an overview of how Outlook stores your e-mail messages, calendar items, contacts, and tasks. Additional help is available that explains how to reconnect an Outlook data file. In addition to your data files, there are other configuration files that you might want to learn about. A listing of Outlook file locations is available in Outlook Help.

Where does it all go?

Where are your e-mail messages saved? Are the messages kept on the e-mail server (e-mail server: A computer that stores e-mail messages.) or locally on your computer in an Outlook data file? The answer depends on the type of e-mail account (email account: The server name, user name, password, and email address used by Outlook to connect to an email service. You set up the email account in Outlook by using information provided by your administrator or Internet service provider (ISP).) that you have and how you configured the account in Outlook. The place where your new messages are saved is called the default delivery location.

ShowMicrosoft Exchange Server e-mail account

If you use a Microsoft Exchange Server e-mail account, typically your e-mail messages, calendar, contacts, and other items are delivered to and stored in your mailbox (mailbox: Location in Microsoft Exchange Server where your email is delivered. An administrator sets up a mailbox for each user.) on the server. When you install Outlook on a new computer and select an Exchange Server account in the E-mail Account Wizard, all your items on the server are again available to you. The remaining information in this article does not apply to you, unless you created archive or local data files, or you specified that your Exchange messages be delivered to a local data file.

Exchange Server accounts also allow you to work offline or use Cached Exchange Mode. If you work offline or use Cached Exchange Mode, local copies of your items are kept on your computer in an Offline Folder file (.ost) (Offline Folder file: The file on your hard disk that contains offline folders. The offline folder file has an .ost extension. You can create it automatically when you set up Outlook or when you first make a folder available offline.). The .ost file is synchronized with the items on your Exchange server. Because your data remains on the Exchange server, you can recreate this .ost file on your new computer without having to back up the .ost file.

ShowDetermine whether Cached Exchange Mode is turned on

  1. On the Tools menu, click E-mail Accounts.
  2. Click View or change existing e-mail accounts, and then click Next.
  3. In the Outlook processes e-mail for these accounts in the following order list, click the Exchange Server e-mail account, and then click Change.
  4. Under Microsoft Exchange Server, if the Use Cached Exchange Mode check box is selected, Cached Exchange Mode is turned on.

Alternatively, you can move or archive your Exchange account items to a Personal Folders file (.pst). You can also configure Outlook to deliver new items to a .pst file, rather than keeping the items on the server. You must back up these .pst files as well as reconnect them to your new installation of Outlook. By default, .pst files are saved in the <drive>:\Documents and Settings\<user>\Local Settings\Application Data\Microsoft\Outlook folder. Although you can keep your data files in any folder, this is the default folder that Outlook uses when creating .pst files.

 Note   This location is a hidden folder. To use Windows Explorer to navigate to this folder, you must first turn on the display of hidden folders. In Windows Explorer, on the Tools menu, click Folder Options. On the View tab, under Advanced Settings, under Files and Folders, under Hidden files and folders, select Show hidden files and folders. If you want to see all file name extensions, clear the Hide extensions for known file types check box. Hidden folders appear dimmed to indicate that they are not typical folders.

ShowDetermine whether the default delivery location is a .pst file

  1. On the Tools menu, click E-mail Accounts.
  2. Click View or change existing e-mail accounts, and then click Next.
  3. Under Deliver new e-mail to the following location, verify the default delivery location that is listed.

Delivery of new e-mail messages to an Exchange server location usually appears as Mailbox - <user name>. Delivery of new messages to a .pst file appears as Personal Folders or a custom display name that you provided for the .pst file.

ShowPOP3, IMAP, and HTTP e-mail accounts

If you use a POP3 (Post Office Protocol 3 (POP3): A common Internet protocol that is used to retrieve email messages from an Internet email server.) e-mail account, which is one of the most common types of personal e-mail accounts, your e-mail messages are downloaded from your POP3 e-mail server at your Internet service provider (ISP) (ISP: A business that provides access to the Internet for such things as electronic mail, chat rooms, or use of the World Wide Web. Some ISPs are multinational, offering access in many locations, while others are limited to a specific region.) to your computer and delivered to and stored locally in a Personal Folders file (.pst) called Outlook.pst. Outlook.pst is the default data file name. The file is stored in the <drive>:\Documents and Settings\<user>\Local Settings\Application Data\Microsoft\Outlook folder.

IMAP (IMAP (Internet Message Access Protocol): Unlike Internet email protocols such as POP3, IMAP creates folders on a server to store/organize messages for retrieval by other computers. You can read message headers only and select which messages to download.) and HTTP (Hypertext Transfer Protocol (HTTP): Protocol that is used when you access webpages from the Internet. Outlook uses HTTP as an email protocol.) e-mail accounts save your e-mail messages on a server, as does an Exchange account. As with any type of Outlook e-mail account, you can choose to archive or move items from the server into a local .pst file. If you archived or moved items from the server to a local .pst file, you need to back up the .pst file and then reconnect to it in your new installation of Outlook. If you kept everything on the server, after you use the E-mail Accounts Wizard to set up your IMAP or HTTP account, all of the items on the e-mail server will again be available to you in Outlook.

Customize the display name of the data file

The default setting for a Personal Folders file (.pst) (Personal Folders file (.pst): Data file that saved your messages and other items on your computer. You can assign a .pst file to be the default delivery location for email messages. You can use a .pst to organize and back up items for safekeeping.) is for the display name to be Personal Folders. This can be confusing if you work with multiple .pst files that all have the same name. A best practice is to customize the display name.

  1. In the Navigation Pane (Navigation Pane: The column on the left side of the Outlook window that includes buttons for the Mail, Calendar, and Tasks views and the folders within each view. Click a folder to show the items in the folder.), right-click Personal Folders, and then click Properties for Personal Folders.
  2. Click Advanced.
  3. In the Name box, type a name that is meaningful to you, such as My Stuff.
  4. Click OK twice.

In the Navigation Pane, you see a top folder with the name that you provided. Now you can quickly distinguish your data file from any others.


Customizing the file names is also useful if you keep multiple .pst file archives. For example, if you create a monthly .pst file to store all of your sent items for that month, you can rename the display name from Personal Folders to something more friendly, such as Sent Mail Archive – December 2004.

Make data files vanish — at least from the Navigation Pane

Even if you are an e-mail packrat, eventually you might want to clear some of the clutter in the Navigation Pane. You might not always need instant access to an archive .pst. You can delete an Outlook data file from the Navigation Pane without deleting the file from your computer. Right-click the Personal Folders file that you want to delete from the Navigation Pane, and then click Close Personal Folders. If the Close Personal Folders option is not available, you are probably trying to delete the .pst file that Outlook uses for saving your new messages.

Afraid of deleting the wrong file? Closing a .pst file doesn't delete the file or any items that it contains. The file just no longer appears in the Navigation Pane. You can always add any .pst file back to the display by doing the following:

  1. On the File menu, point to Open, and then click Outlook Data File.
  2. Click the .pst file that you want to open, and then click OK.
Applies to:
Outlook 2003