Steps to Convert OST to PST Without Outlook – Free & Paid

  • Written By  

  • Updated on April 25th, 2025

Have you ever tried to access OST files without having MS Outlook? There are many scenarios when users face problems retrieving important data from OST files. Such issues arise especially when the Exchange server crashes, is being migrated, or the OST files are orphaned. The most efficient way to overcome such situations is converting OST files to PST. You can find multiple solutions to do it manually. However, if you are not an Outlook user, the FRT Freeware OST Converter will let you convert OST to PST without Outlook. Let’s plunge into all possible ways, from free to professional software.

Understanding Outlook Data Files- OST and PST

As you know, OST and PST are data files of Outlook. Here is a quick overview of both files before you begin to convert the OST file to PST format. 

OST Files: OST or Offline Storage Table synchronizes Exchange Server accounts including Outlook 365 with your PC (local machine).

  • This file is proprietary to the Exchange Server and therefore not compatible with other platforms.
  • Enables offline access to Outlook mailbox data including emails, contacts, and more.
  • It automatically syncs the changes made offline once the connection is established and ensures that data consistency is maintained.
  • Limitation: OST file cannot be used for backup of Outlook mailbox. 

PST Files: PST, or Personal Storage Table, is an Outlook data file used for managing mailbox data. It is also ideal for backing up email account types like POP3, IMAP, and web-based accounts.

  • PST acts as a local backup of Outlook mailbox data and is preferred for sharing Outlook emails and others.
  • It works independently and does not require a server connection for regular synchronization.
  • Outlook PST files are easily portable and flexible to use across multiple email platforms and systems.
  • Limitation: Large and oversized PST files are prone to corruption, risking crucial data loss.

Why do You Need to Convert OST to PST?

Being an Outlook user, you might have faced different scenarios when conversion of OST to PST is required. Whether you have a personal account or a business account, the following could be possible reasons:

  • Due to unexpected issues when the Exchange Server faces downtime, you cannot open the OST files. Saving Outlook emails to PST, you can access them in local mode. 
  • PST is also the preferred format for backup of Outlook mailbox and sharing them across different platforms or systems. Backup files server during accidental deletion or sudden mishaps.
  • You can also archive older Outlook emails in PST and free up server space from OST. Hence, Outlook runs faster and smoother.
  • In case the OST file gets corrupted or inaccessible, users can recover the remaining mailbox data in Outlook PST.

Besides, there are many advantages of PST files which is why users export OST to PST. Let us proceed to a solution.

Multiple Effective Methods to Convert OST to PST

Conversion of OST files to PST can be carried out using both Outlook and without Outlook. Many users who do not have access to MS Outlook find it difficult. Therefore, one can use professional software discussed later. 

Method 1: Export OST to PST using MS Outlook

This manual method is free of cost, however, it requires Outlook installation and account configuration. Outlook has a built-in feature Import/Export. Do as the steps follow:

  1. Launch Outlook for Windows and go to File.
  2. Click on Open & Export and then, the Import/Export tab. 
  3. Import and export Windows opens. Opt Export to a file > Next.
  4. Choose the Outlook Data File (.pst) file type to export > Click Next.
  5. Next, select the mailbox folders/items to export into a PST file.
  6. Tick the Include subfolders checkbox, ensuring all emails are transferred.
  7. Specify the filters like date range or sender/recipient per requirement.
  8. At last, click Next to confirm the conversion.
  9. Define a location on your system to save Output PST.
  10. Enter a name for the output file and click on Finish.

Depending on your Outlook mailbox size, the process may take some time. Also, it is not an ideal solution for bulky mailboxes and large attachment migration. 

Method 2: Auto-Archive Feature Convert OST File to PST File

Outlook also has an inbuilt Auto-Archive option that moves OST emails automatically to PST files. Hence, it helps in better management of emails. Follow the process given:

  1. Go to File in the Outlook application > click on Options.
  2. Select the Advanced option and choose AutoArchive.
  3. In the Run AutoArchive every section, select the Archiving frequency.
  4. Browse the path where you want to save the archived PST file.
  5. Go to the Archive items older than section, and specify the age of e-mail messages to be auto-archived.
  6. Select the ‘Use .pst file’ option if you want to save the archive as PST.
  7. Click on Start AutoArchive to start the auto-archiving process.
  8. Finally, click on OK to apply the AutoArchive settings.

Restriction of Manual Method

Here are reasons which is why you should not change OST to PST using manual ways:

  • You cannot batch-export OST files with this manual procedure. 
  • Manually converting large OST files will take significant time and is complex.
  • It may risk losing important data including metadata and folder structure. 
  • Exporting large OST files can be daunting and may lead to incomplete migration.
  • These procedures require Outlook account configuration and are limited to Outlook users.
  • Some steps may vary depending on which Outlook version you are using. 

Would you like to risk your important Outlook data with the manual method? Obviously, no one will. Therefore, the best alternative is to use professional software designed to convert OST file to PST without Outlook. You might think it’s difficult to operate, but this is not so. Let us see how.

Method 3: Secure Software to Convert OST to PST Without Outlook

Built with an advanced algorithm, FRT Freeware OST Converter Software is the best solution. It is a dedicated tool that does not require Outlook installation and is for all technical and non-technical users. The tool allows the conversion of multiple OST files at a time and that too without any size limitations. Irrespective of any Outlook version, the tool supports all OST and PST files and is widely compatible with all versions of Windows OS.

Convert Outlook OST File to PST Using the Tool

Follow the procedure of the software to convert OST:

  1. Install the FRT Freeware OST Converter Software on your PC.
  2. Browse and add OST files that you want to convert.
  3. See the added OST files and mailbox data in the Preview panel.
  4. Choose the export option ‘Save as PST’ and define a saving location.
  5. At last, click on Convert Now to begin migration from OST to PST.

Why OST Converter is the Best Solution?

  • The software supports batch conversion of multiple OST files.
  • Shows preview of Outlook emails before conversion.
  • Quick and secure solution to convert large and bulky OST files.
  • Compatible with all Windows PC, including the latest Windows 11.
  • Converts OST files created by any version of MS Outlook.
  • It has a self-explanatory GUI for all non-technical and novice users.

With a number of such features, the tool is the top choice for you.

Conclusion

Hopefully, this blog will help you effortlessly convert OST to PST. It includes various manual approaches using Outlook Import/Export or Auto-Archive options. However, this manual approach has some drawbacks like time-consuming, risk of data loss, and more. Therefore, professional software is faster and hassle-free, especially for handling large or multiple PST files. One can easily convert and manage bulky OST files with ease. You must choose the right approach that will keep your email data preserved, accessible, and secure.

Frequently Asked Questions-

Q. How to download free OST to PST Converter?

Ans- It is very easy to download a free OST to PST Converter. Simply search for “FRT Freeware OST Converter” and open the webpage. On the page, you will find a “Free Download” button with a Download sign. Click on the button, and the software will be successfully downloaded, and ready to install. 

Q. What is the free tool for converting OST to PST?
Ans- There is such free software to convert OST files for free. You can use FRT Freeware OST Converter demo tool. It free software for evaluation of the software’s functionality but can also convert OST files with ceratin restriction. For migration of multiple OST files to PST, prefer purchasing the premium license.

About The Author: