subject: Ost File Created In Ansi Format Instead Of Unicode Format In Exchange 2003/2000 [print this page] A lot of trouble happens when you transfer your MS Exchange Server environment. Both OST and PST files need to be handled carefully. Consider one of the common scenario in which when you move your Microsoft Exchange Server 5.5 mailboxes to a computer running MS Exchange Server 2003 or 2000 Server, users Offline Storage folder .OST file and offline Address Book files remain in ANSI format (American National Standards Institute). You expect the offline folder file and the offline Address Book file to be downloaded in Unicode format but its not, which is a cause of concern.
If you recreate a user's MS Outlook profile and then obtain and synchronize a new offline folder file with the user's offline Address Book file, the offline folder file and the offline Address Book file use Unicode format.
Reason behind this issue
In Exchange Server 5.5, a cached offline folder .OST file is created in ANSI format and so is Offline Address Book file. This file has a two gigabyte (GB) size limit. When you move the mailboxes from your Exchange Server 5.5 computer to a computer that is running Exchange 2003 or Exchange 2000, the cached offline folder files that are in ANSI format doesnt get automatically recreated in Unicode format.
Resolution
To resolve this issue, you are supposed to use Group Policy for incorporating the use of Unicode format for MS Office Outlook 2003. And to do so, follow the given below steps:
Install the Microsoft Office 2003 Editions Resource Kit.
On a domain controller, start the Active Directory Users and Computers snap-in.
Right-click the domain or organizational unit container where you want to configure the Group Policy object, click Properties, and then click the Group Policy tab.
Add a new Group Policy object, or edit an existing Group Policy object.
In the Group Policy Object Editor tool, expand User Configuration, right-click Administrative Templates, and then click Add/Remove Templates.
Click Add, click OUTLK11.ADM, click Open, and then click Close.
Under User Configuration, expand Administrative Templates, expand Microsoft Office Outlook 2003, and then click Exchange Settings.
In the right pane, double-click Exchange Unicode Mode - Ignore OST Format.
Click Enabled, and choose one of the following
Create new OST if format doesn't match mode
Prompt to create new OST if format doesn't match mode
Click OK, and then quit the Group Policy Object Editor tool.
Whenever OST file gets corrupt, one need to recover OST file, which is achieved by converting OST to PST file. Advanced OST to PST conversion software is available which simplifies the process of conversion from OST to PST and hence recovers the corrupt OST file.
