Repair an .ost or .pst file in Outlook

APPLIES TO
Microsoft Outlook® 2002

If you are keeping Outlook data on your computer, you are using a Personal Folders file (.pst) or an Offline Folder file (.ost). To prevent data loss, you need to know how to repair these files.

If your .pst file becomes damaged, Outlook includes a tool that may be able to correct the problem without your switching to a backup copy. This tool, the Inbox Repair Tool, is installed on your hard disk when you install Outlook.

If your .ost file becomes damaged, Outlook includes a tool that may be able to correct the problem. This tool, the OST Integrity Tool, can scan and repair .ost files. If that doesn't completely solve the problem, you can disable the .ost file and create a new one.

REPAIRING A PERSONAL FOLDERS FILE (.PST)

You may need to use the Inbox Repair Tool if you open your Outlook .pst file and receive this message:

Unable to expand the folder. The set of folders could not be opened. Errors could have been detected in the file drive:\Documents and Settings\user\Local Settings\Application Data\Microsoft\Outlook\Outlook.pst. Quit all mail-enabled applications, and then use the Inbox Repair Tool.

 NOTE   The path to the file specified in the message may vary depending upon the operating system you are using on your computer.

To repair the .pst file

1. On the Start menu, click Run.
2. In the Open box, type

drive:\Program Files\Common Files\System\Mapi\LocaleID\scanpst.exe

where LocaleID is the locale identifier (LCID) for your installation of Microsoft Office. For example, the LCID for English (United States) is 1033. For a list of LCIDs, see Microsoft Office Help.

3. Click OK.
4. In the Enter the name of the file you want to scan box, type the path and file name given in the error message above.

 NOTE   You may not be able to use the Browse button to locate this file because it is located in a hidden folder.

5. To change the options for logging errors during the scan, clickOptions. If you choose Replace log or Append to log, the log file is saved to the same directory as the .pst file.
6. Click Start.
7. When the file scan is completed, select the Make a backup of scanned file before repairing check box.
8. Click Repair.

If the file is successfully repaired, you will see a Repair complete message. If the Inbox Repair Tool was unable to repair the file, you will need to use a backup of your file.

To begin using your backup file as your new primary file

1. Start Outlook.
2. On the File menu, click Data File Management.
3. Select the .pst that is damaged, and then click Remove.
4. Click Add, select Personal Folders File (.pst), click OK, and then select the .pst file you want to use as the new primary file.
5. Click OK.

 IMPORTANT    You should not rely solely on the Inbox Repair Tool for disaster recovery. A system of regular backups of your .pst file is an important part of preventing data loss. You can back up the file in several ways, including copying it to another location, backing up all of the files on your computer, or by using the Personal Folders Backup utility, available on the Microsoft Office Online site.

REPAIRING AN OFFLINE FOLDER FILE (.OST)

You may want to scan and repair your .ost if you:

• Encounter a large numbers of conflict items.
• Cannot open particular Outlook items when offline.
• Receive unexpected synchronization error messages (as shown in the synchronization log in the Deleted Items folder).
• Receive the message:

Unable to expand the folder. The set of folders could not be opened. Errors could have been detected in the file drive:\Documents and Settings\user\Local Settings\Application Data\Microsoft\Outlook\Outlook.ost. Quit all mail-enabled applications, and then use the Inbox Repair Tool.

 NOTE   The file path specified in the message may vary depending upon the operating system you are using on your computer.

In addition, you might be able to open folders in the .ost but get synchronization error messages that do not go away. This happens when a single e-mail message is damaged and the synchronization process cannot correct it. You can use the OST Integrity Tool to fix damaged messages or to move them so you can synchronize successfully.

 IMPORTANT   You may need to run scanpst.exe (see the first procedure above) first if the OST Integrity Tool cannot open the .ost file.

To scan and repair the .ost file

1. Close Outlook.
2. On the Start menu, click Run.
3. In the Open box, type

drive:\Program Files\Common Files\System\Mapi\LocaleID\scanost.exe

where LocaleID is the locale identifier (LCID) for your installation of Microsoft Office. For example, the LCID for English (United States) is 1033. For a list of LCIDs, see Microsoft Office Help.

4. Click OK.
5. Click either Scan all folders or Choose folder to scan. If you clickScan all folders, this may take several minutes.
6. Select the Repair errors check box.
7. Click Begin Scan.

Details of actions performed during the scan and repair are saved as a message in your Outlook Deleted Items folder with the subject "OST Integrity Check."

If the Offline Folder file cannot be repaired, you can disable it and create a new one.

To disable the .ost file and create a new one

1. On the Tools menu, click E-mail Accounts, click View or change existing e-mail accounts, and then click Next.
2. In the list, click Microsoft Exchange Server, and then click Change.
3. Click More Settings.
4. Click the Advanced tab, and then click Offline Folder File Settings.
5. Click Disable Offline Use.
6. In the File box, type the path to the file you want to use as the new .ost file. The default file name is outlook.ost. If this file name already exists, you are prompted for a new name.