For Microsoft Outlook 2007, see Microsoft Outlook 2007 Backup and Dual Boot File Locations. Includes file locations in Vista and Windows 7. Outlook 2010's backup information is at Microsoft Outlook 2010 Backup and Dual Boot File Locations.

Where is my Microsoft Outlook data stored, people often ask? Your Outlook folders are either in a mailbox on a Microsoft Exchange Server or in Personal Folders .pst files on your system. You may also have a Personal Address Book .pab file if you use an older version of Outlook, however we recommend you import it into your Contacts folder as it is no longer supported.

Backup and dual-booting between Windows versions all involve using the same files. There is no backup process built into Outlook. To back up, simply exit Outlook, then copy the files you want to back up. Below we provide a chart of Outlook 2000/2002/2003 file locations, followed by notes on particular files and where they might be found in earlier versions.

These files are also the ones that you'd want to copy back and forth between machines if you need to use the same information at the office and at home, for example. If you have Outlook profiles, name them the same on both machines, so you can use the same .fav and .rwz files. Then use Tools | Services (or Tools | Accounts) to point the Personal Folders and Personal Address Book services to the files that you've copied.

See Moving Outlook to a New Computer for the steps needed to move Outlook files to a new computer.

See How to move the IMAP personal folder (*.pst) for the proper way to move IMAP and Internet Subscription folders.

If you dual-boot, use the same profiles in each operating system. Your profile can point to the same .pst, .ost and .pab files, but you would need to copy the .fav, .rwz and .rtf files and the Outlprnt file.

Outlook 2003 File Locations | Personal Folders Files | Offline Folders File
Personal Address Book | Other Files | Accounts | Tools | Notes | More Information

Outlook 2003 File Locations

Where do you find these files? You can always start by using your operating system's Search or Find command to locate the particular file types. You may need to change Windows File Explorer options to Show hidden files and folders.

Under Outlook, most files will be in a subfolder under the Application Data folder on your system, though the exact location of the Application Data folder can vary.

When using modern Windows versions, Outlook stores *.pst, *.ost, *.msnpst, *.pab, *.oab, and extend.dat in C:\Documents and Settings\<username>\Local Settings\Application Data\Microsoft\Outlook. Extend.dat cannot be moved. See How to move the IMAP personal folder (*.pst) for the proper way to move IMAP and Internet Subscription folders.

All other Outlook configuration files are stored in C:\Documents and Settings\<username>\Application Data\Microsoft\Outlook and cannot be moved.

Tip: Type or paste these lines in Windows Explorer address bar to open the folders:

To access the folder holding the toolbar, VBA, rules, and nickname files, paste:

%USERPROFILE%\Application Data\Microsoft\Outlook

To see the message store files, paste:

%USERPROFILE%\Local Settings\Application Data\Microsoft\Outlook

Beginning with Vista, the appdata folders move to C:\Users\username\AppData for data storage, with the Local and Roaming subfolders. Outlook 2007 File Locations has more information on the files stored in the Local and Roaming subfolders. Use %appdata%\Microsoft\Outlook or %localappdata%\Microsoft\Outlook shortcuts.

Note: Storing Personal Folders on a network file share is not recommended and may cause corruption and data loss.

Personal Folders Files

If you are not connecting to Microsoft Exchange Server, all your Microsoft Outlook data is stored in one or more Personal Folders (.pst) files.

In Outlook 97 and Outlook 98 or Outlook 2000 in Corporate/Workgroup mode, check the properties for Personal Folders in Tools | Services (or Tools | Account Settings) to determine the exact location on your system.

In Outlook 98 or Outlook 2000 in Internet Mail Only mode, right-click on Outlook Today or the top level of any other set of folders and then choose Properties.

Some people like to export a folder, such as Contacts, to a separate backup .pst file. That's fine for the data, but it does not back up any folder customizations such as views and custom forms. If you want to back up those, too, copy the entire folder to a new .pst file instead of using the export feature.

Also see Limits to using personal folders (.pst) files over LAN and WAN links

Offline Folders File

If you do use Microsoft Exchange Server, you may have an offline folders (.ost) file. You shouldn't need to back it up, since you can always refresh it by synchronizing with the server. However, be sure you understand the procedure for Recovering data from offline folders. If something ever goes wrong with your Exchange Server mailbox, this technique can save time and information, but you must apply it before you try to connect to the server again.

Personal Address Book

The Personal Address Book (.pab file) can be used to store addresses in Outlook 97 and Outlook 98 or Outlook 2000 in Corporate/Workgroup mode. Again, check Tools | Services to see if you're using a PAB and where it's located.

Note that the PAB is deprecated and may not be supported in future versions. For this reason you should import the contents to your Contacts folder and remove it from your profile.

Other Files

You may want to back up the .fav, .rwz and .rtf files ne for each profile on your machine. These are the Outlook Bar shortcuts, Rules Wizard rules and rich-text format AutoSignature files, respectively.

Some other miscellaneous files, not necessarily worth backing up

• Extend.dat -- Information about installed add-ins. Will be recreated if you delete it.
• Outitems.log -- Outlook items to be placed automatically in the Journal
• Offitems.log -- Office items to be placed automatically in the Journal
• Outform.dat -- Information about Outlook forms (not sure what it does)
• Outlook.box -- Custom control toolbox for forms design.
• Frmcache.dat -- Outlook forms cache file. See How the Microsoft Outlook forms cache works.

Accounts

Account information is held in the user's Windows registry, not in a file. If Outlook 98 or 2000 is in Internet Mail Only mode, you can use the Tools | Accounts | Export to export account details, but not passwords.

Notes

If your network is set up so that you can use Outlook at any machine ("roaming profiles"), your Outlook files may be in a different location. Try using Start | Find to locate each type of file. If you don't see any .pst files after you search, you may need to adjust the settings in Windows Explorer to show hidden and system files. Choose Tools | Folder Options, then switch to the View tab, and select Show hidden files and folders.

Personal Folders .pst files are among the files that are normally not included in a Windows 2000 (or later) offline files synchronization. However, you can edit the system policy that controls the file types so that .pst files can be included.