Why You Need to Convert Outlook OST to PST

MS-Outlook caters to a wide range of messaging needs of a business organization and is widely used in offices for internal and external communication. Most of the users have an MS-Exchange Server account which works in synchronization with an offline storage table file (.OST). The OST file contains all your mail items in an offline mode on your hard drive. Every time you log in to your account, all the mail items are synchronized and downloaded into this. These OST files work in synchronization with the MS Outlook PST file. It helps in keeping the mailbox up-to-date with new mails, meeting request, delivery reports etc. However, there are situations when such mail items become inaccessible. In such a situation, you need to convert mails in the OST file into a different Outlook compatible file format like PST.

Some of the reasons, when it becomes necessary to import ost into pst, are mentioned below.

  • MS-Exchange server can unexpectedly crash due to power failure, malicious software, virus attacks, or any other reason. A severe crash could land you nowhere as you might not be able to connect to the MS Exchange Server. Such situations are very challenging and difficult to handle as in most of such cases they result in repeated display of various error messages.
  • In the case of Exchange Server downtime or Exchange Server maintenance, you will not be able to access your mailbox. However, at times it becomes very necessary to have access to the mailbox items. All the user mailboxes, which include different mail items, are stored in an OST file, which works with synchronization with MS Exchange Server. To access the mail items, you need to export ost to pst and import it to MS Outlook application.
  • By converting Outlook OST to PST file format, the data can be recovered even after accidental deletion of user mailboxes on the Exchange server.
  • Converting OST to PST helps in migrating the data from one place to another. This is very helpful in case the organization is shifting, or you want to move your important data on a different system.
  • While working with an MS Outlook client, you might come across the following error messages.
  • 'Your offline folder file could not be configured.\\ComputerName\FolderName\Outlook.ost.'
  • 'The operation failed due to a registry or installation problem. Restart Outlook and try again. If the problem persists, please reinstall.'
Also, the following message might appear when you are working in a networked environment and the system having the OST file is not shared.

"ComputerName is the computer name on which installation of Microsoft Outlook has been done and FolderName is the name of the folder that includes the offline file."


Since OST files are the offline storage files, which let you send/receive and delete emails even when it is not connected to Exchange Server. Once connected, it gets synchronized with the Exchange Server. That means all the changes that have been made to the OST file while working offline will be reflected in the Exchange Server. However, this OST file might get corrupt. This will lead to inaccessibility to user mail items. The OST file gets corrupt due to several reasons, as mentioned below.

  • Software related issues
  • Unexpected hardware failures
  • Abnormal termination
  • Application shutdown
  • Damage induced on the database
  • Server breakdown
  • Virus Attacks
  • Trojans Infections
  • Lack of Storage Space
  • Accidental deletion of the user account
To overcome this situation, you need to repair the OST file. However, you may not get the best tool to repair a corrupt OST file; hence, the only best way is to convert a working outlook ost to pst. For this, you can use the backup copy of the OST file. The PST is a file format that can store all the mail items from the OST file and you can continue working.


Such process might resolve the issue, but any manual conversion is never recommended; as they are always prone to errors and lacks a professional approach. The process requires a professional tool that can convert OST file into PST format. The best option here is to use a reliable and tested professional tool.

Stellar Converter for OST proves to be an ideal tool to extract PST from OST without any hassle. It uses a self-explanatory interface, which guides the user to easily convert all OST files to PST files. Once done the converted PST files can be imported back to the MS Exchange Server in a single step. This helps in saving a lot of time and cost, which was involved in the rebuilding process. The tool supports all MS-Outlook versions released till date including the 32 and 64-bit versions. With this tool, you can retain the access to all mail items including messages, notes, attachments, contacts, calendar, journal, etc.

Also, the tool allows you to save the converted emails in various other message formats like EML, MSG, RTF, etc. Moreover, you can quickly preview the mail items before the conversion process. This helps in the selective conversion of various mail items like emails, notes, attachments, and contacts to PST.

  • Converts corrupt or inaccessible OST file to a usable PST
  • Restores mail items like attachments, tasks, notes, journals, calendar, etc.
  • Provides quick preview of mail items
  • Supports selective conversion of mail items
  • Provides advanced "Find" feature to search OST files
  • Options to save mail messages in different formats including EML, MSG, PST, RTF, HTML, and PDF
  • Provides a self-explanatory and interactive graphical user interface
  • Widely compatible with MS Outlook 2021, 2019, 2016, 2013, 2010, 2007, 2003, 2002, and 2000


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About The Author
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Shelly Bhardwaj linkdin Icon

Shelly is technology expert and core knowledge of Exchange Server, Outlook.

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