Making regular backup files of any important data you have is always a good idea. One way to back up e-mail messages is to use the Outlook AutoArchive feature. Archiving means moving messages to an archive folder at regularly scheduled intervals.

Another way to make a backup file, which is described in this article, involves exporting (copying) the contents of the message folder to a Personal Folders file (.pst) (Personal Folders file (.pst): Data file that stores your messages and other items on your computer. You can assign a .pst file to be the default delivery location for e-mail messages. You can use a .pst to organize and back up items for safekeeping.) using the Import and Export Wizard. This creates the backup .pst file. You can then copy the .pst file onto a CD or DVD for safekeeping or to move the data to another computer with Outlook installed.

This steps work on outlook 2003.

1. On the File menu, click Import and Export.
2. Click Export to a file, and then click Next.
3. In the list, click Personal Folder File (.pst), and then click Next.
4. Click the folder that contains the messages you want to back up. If the folder contains a subfolder that you want to include, select the Include Subfolders check box, and then click Next.
5. Under Save exported file as, click Browse, and then specify a name and location for your backup file, for example, Mail Backup.
6. If you back up a .pst file that you have backed up to before, click one of the following:Replace duplicates with items exported Existing data will be overwritten with the information in the file being exported.Allow duplicate items to be created Existing data will not be overwritten, and duplicate information will be added to the backup file.

   Do not export duplicate items Existing data will be kept, and the duplicate information in the folder will not be copied to the backup file.

7. Click Finish.