XCLN: Restoring from an OST after Deleting the Mailbox

• Microsoft Exchange Windows 3.x client version 4.0
• Microsoft Exchange Windows 3.x client version 5.0
• Microsoft Exchange Windows 95 client version 4.0
• Microsoft Exchange Windows 95 client version 5.0
• Microsoft Exchange Windows NT client version 4.0
• Microsoft Exchange Windows NT client version 5.0

SUMMARY

Offline Folder files (OSTs) are considered slave replicas of the server- based folders. If you delete the master, the slave is orphaned.

If the original Microsoft Exchange profile was not modified, you should still be able to start the Microsoft Exchange client offline with the old OST and recover the data by moving the messages from the OST to a PST file. However, if the old profile was deleted or modified (by using it to log onto a different mailbox) then the data in the OST is lost.

MORE INFORMATION

It is possible to recover mail stored in an OST provided you have not tried to modify the profile that was used to create the OST file. If the profile used to create the OST file has been modified to point to a new mailbox, the information contained in the OST file may be lost.

The reason for this is due to how security on an OST works because Windows NT authentication cannot be used when working offline. Therefore, you must "prove" that you're allowed to log onto the server-based master before the OST file will give you local access. Microsoft Exchange does this by creating an encrypted "cookie" from your mailbox's unique entry ID while you are successfully logged into the Microsoft Exchange Server. This cookie is securely stored in your Microsoft Exchange profile. Essentially, your profile stores this key for the OST. Every time you try to access the OST file it checks your profile for the existence of this key.

By modifying the profile or trying to connect to a new mailbox or new server with the current profile, Microsoft Exchange replaces this key with a new value from the mailbox that was created. At this point, there is no method to get into the data that was contained in the OST created against the first mailbox.

For more information, see the Microsoft Exchange Disaster Recovery Document on Microsoft TechNet or on the Internet at:

   http://www.microsoft.com/exchange/support/deployment/planning/deploy.asp

Steps to recover

If you have not modified your profile or attempted to log in online to the new mailbox, use the following steps to copy the offline messages into a PST.

1. Start the Microsoft Exchange client up OFFLINE.

   step 4.

At this point, the messages are copied to a PST. A new profile can be created and you can login to the new server based mailbox. Once this is completed successfully, a Personal Folders service can be added (referencing the PST created above), the messages can be copied from the PST back to the server based mailbox.

Note - Offline Folders (OST's) should not be considered as backups of your server based store. For more information on proper server backups, refer to the Microsoft Exchange Administrator's Guide - Chapter 15

Keywords          : XCLN kbusage
Version           : 4.0
Platform          : winnt