How to Convert an Orphaned OST to a PST

Apart from Online connection mode, Microsoft Exchange Server also supports an Offline client connection mode, in which the changes that are done at the client workstation are synchronized at the time of next connection between the Exchange Server Information store and client file. In such cases, Microsoft Exchange Server creates an offline folder file (.ost file) at the client workstation, which is similar to the personal folders file (.pst file), but can be automatically compressed. At client workstation, .ost file remains unreadable until a synchronization with Exchange Server is successfully completed and the file is converted to a readable .pst file. But there are situations, which if occur, can create the problem of an orphaned .ost file. Such problems can be resolved using solutions like, a Convert OST utility. This article mentions the circumstances that can cause these problems and also the possible solutions.

In Offline connection mode of Exchange Server, a mailbox encryption key is placed at two different locations, which are MAPI profile and the mailbox itself. An OST file gets orphaned if this key is lost from both the locations. The reason is Exchange Server checks this key at these locations when the client tries to connect with Exchange Server in the online mode. If the keys are lost, OST file will not be allowed to synchronize with Exchange Server, resulting in the file becoming unusable. This typically occurs when any of the following problems steps-in:

1)Exchange Server administrator deletes the user mailbox or the mailbox account

2)Exchange Server goes down or crashes

3)Domain name changes

4)MAPI profile is changed

5)Microsoft Exchange Migration Wizard is used to migrate a mailbox

6)Exchange Server is migrated

7)Exchange Server is decommissioned

If you encounter any of the above situations and the original MAPI profile exists, there are chances that you can extract data from the orphaned OST file to a PST file by reconnecting the file to this profile and connecting it to original Exchange Server. However, if no suitable profile exists, you should use a third-party OST to PST utility. A Convert OST software can scan the orphaned OST file and convert it back to a usable PST file without any aid from the Exchange Server.

Stellar Phoenix Mailbox Exchange Desktop is a comprehensive solution that converts an unusable OST to PST. It supports MS Outlook 2007, 2003, 2002, and 2000 and can extract e-mails, contacts, calendar entries, and all other items using safe algorithms.