Manual OST to PST Conversion using Outlook – 2 Free Methods
Updated On - September 30, 2026 by Armaan | Reading Time: 8 minutes
Quick Answer
You can convert an accessible OST mailbox to PST using Outlook’s built-in Export feature. Open Outlook → File → Open & Export → Import/Export → Export to a file → Outlook Data File (.pst), select the required folders, enable Include subfolders, and save the PST file. Manual methods require an accessible Outlook profile and may not work with orphaned or corrupted OST files. For inaccessible, orphaned, or corrupted OST files, Regain OST to PST Converter can be used to convert the OST data directly to PST.
Summary: Outlook is the most popular and useful email client where you get all your essential emails from your business partners or clients. Many users complain that their OST files get corrupted somehow, and they do not know how to repair them.
In this article, we will go through all the possible solutions and methods for OST to PST Conversion manually. Go through all the steps to export offline OST data files to Outlook PST files. We will also mention a Regain OST to PST converter tool to convert damaged or corrupted OST files to PST.
Why do your OST files get corrupted?
Over the internet, there are numerous reasons that your OST files get damaged or corrupted, and here we will mention the possible errors that will harm or corrupt your OST files.
- Malware or virus attacks
- Accidental power off the system.
- Auto crash Outlook profile while working.
- Bad sectors in the hard drive.
- Incompatible Outlook version
Why do users need to Export OST to PST files?
Exchange server corruption: Occasionally, the MS Exchange server is corrupt for various reasons; in that case, you cannot connect your Outlook emails to the Exchange server. To fix the Exchange server corruption issue, convert OST to PST manually.
Remove the Exchange Server account: When you accidentally remove your Exchange server account, all your OST data, i.e., emails, contacts, tasks, and other files, becomes inaccessible. To get backup all data need to convert ost to pst file.
Migrate Data from one place to another place: However, when your previous Outlook account gets corrupted, you want all your OST files in a new one. Make a backup copy of the PST file to regain all your data in the new account.
If you are worrying about how to convert OST to PST file manually? Then, don’t worry; we will recommend one of the best third-party Regain OST Converter tool to convert OST into PST files.
Top 3 Methods for OST to PST Conversion Manually
Here we discuss Two Manual Methods and One Professional tool to migrate OST to PST files. You can select anyone which suits you.
- 1st Method: Use Auto Archive to Convert OST to PST file
- 2nd Method: Use Import/Export Feature in Outlook
- 3rd Method: Use Professional Regain OST Converter tool
Method 1: Use Auto Archive feature to Convert OST to PST file
The first method to convert OST to PST is to enable archiving in Outlook once your Exchange account is configured. When you enable archiving in Outlook, it automatically moves archived email into a new PST file format and helps maintain an optimal mailbox size.
Here, you need to follow the steps to configure Outlook archiving.
- Step 1: Open Outlook and hit the “File” option.
- Step 2: Click on the “Advanced” option, and a new wizard will open on the screen; select “Auto Archive Settings” in the “Auto Archive.”

- Step 3: In a new Window, select the number of days to run auto-archiving and hit “OK.”

- Step 4: Save your mailbox items from the OST file to PST by enabling the archiving option.
Method 2: Use Import/Export feature
All MS Outlook versions are embedded with built-in import and export, allowing users to transfer OST data to a PST file quickly. This method only works when your OST file is connected to the Exchange Server while exporting. Also, it is useful when making a local and portable backup of Exchange Mailbox data.
Follow these steps to use Import/Export feature in Outlook:
- Step1: Launch the MS Outlook application. Click on the ‘File’ tab >> “Open & Export” >> “Import/Export.”

- Step2: Choose the “Export to a file” option and click the “Next” button.

- Step3: Select the “Outlook Data File (.pst)” option, then click on “Next.”

- Step4: Select the folder you want to convert into PST files and tap Next.

- Step5: Click the “Browse” section to choose the destination folder where you want to save the PST file in your system. Now, hit the Finish button.

- Step6: Add a password to your converted PST file or continue without it. The conversion process will start and end as per the data size.
Both methods will work when your data is low. To continue this method, you need Outlook permanently connected to the Exchange Server; therefore, it does not convert orphan, corrupted OST files. The possibility of data loss during conversion is also common in these manual methods.
However, many users claim they lost some of their data in that PST file. But if you don’t want to face any issues during OST to PST Conversion, I strongly recommend using the third-party OST to PST Converter tool developed by Regain Software. It is an excellent tool with a wide range of features to make the conversion task quick and easy without losing your data.
When Manual OST to PST Conversion Works
Manual export works when:
- The Outlook account/profile is still accessible.
- The OST data is synchronized and available in Outlook.
- Outlook can open and access the mailbox.
- You can select the mailbox/folders for export.
- You have enough disk space for the resulting PST.
When Manual Conversion Does Not Work
Manual Outlook export isn’t suitable when:
- The OST is orphaned.
- The original Outlook profile/account is unavailable.
- The OST file is severely corrupted.
- Outlook cannot access the mailbox data.
- You need to process multiple standalone OST files.
Method 3: Use Professional tool to Convert OST to PST
One alternate solution to Convert OST to PST is “Regain OST File Converter” software. This tool allows you to convert OST files to PST quickly, and it is enhanced with some wide-ranging features that can save you much time. For a better understanding, let’s look at the key features of this tool.
Free Download100% Secure Buy NowPrice: $29
An Expert Solution…
- Instantly Convert the OST file to PST format
- Repair OST File whether it is Corrupt or inaccessible
- Converts Single or Bulk OST files in a few clicks
- Supports selective conversion of Exchange OST files
- Have user-defined and Date-Based Filter options
- Save converted OST into PST, MBOX, PDF, vCard, HTML, EML, MSG, and many more
- Import OST Emails to Office 365, Gmail, Yahoo Mail, Outlook.com, and Live Exchange Server.
- Convert Any Size of OST file, with No file size limit
- Show a Preview of Convertible OST Emails before Saving
- Allow Users to Save 30 Emails per Folder Free of Cost
- Support all versions of MS Outlook & Windows OS
Step by step guide to convert OST to PST using Regain OST Converter tool:
- Step 1: Open OST to PST Converter tool.

- Step 2: Browse and Add damaged or corrupted OST files in the tool.

- Step 3: Now select the Folders on displaying windows that you want to convert into PST files and tap on Export.

- Step 4: Browse the destination folder to save your PST file in your system.

- Step 5: Click on Convert Now to start the conversion task.

- Step 6: If you want to import OST to the Cloud platform, Click the Cloud Migration button and select email client.

Video Tutorial for OST File Conversion Using Regain Software – Watch Now!
Conclusion
This article covers all the possible ways to convert OST files to PST format. If the methods mentioned above do not work correctly, there might be severe corruption in your OST files. Try the Regain OST to PST Converter tool and quickly export all your OST files into PST. This tool is very effective in converting multiple OST files at a time. Also, you can upload PST files in the cloud after exporting.
Frequently Asked Questions
Q1. Can I convert OST to PST manually without third-party software?
A. Yes. If the Outlook account and OST data are accessible, you can use Outlook’s built-in Export feature to save mailbox data as a PST file.
Q2. Do I need Outlook to convert OST to PST manually?
A. Yes. Manual conversion requires an accessible Outlook profile and mailbox. If the OST is orphaned or inaccessible, manual Outlook export generally cannot process it.
Q3. Can I convert an orphaned OST file to PST manually?
A. No. Outlook’s built-in export method requires access to the original mailbox/profile. For an orphaned OST file, use a dedicated tool such as Regain OST to PST Converter.
Q4. Can I convert a corrupted OST file to PST?
A. If Outlook can still access the mailbox, you may be able to export the available data. If the OST is severely corrupted or inaccessible, a specialized OST recovery and conversion tool such as Regain OST to PST Converter can be used.
Q5. Does OST to PST conversion preserve attachments?
A. Yes. Outlook’s PST export includes email attachments and supported mailbox data. However, some Outlook settings and metadata, such as rules and folder permissions, are not exported.
Q6. Can I convert multiple OST files to PST manually?
A. Outlook’s built-in export process is designed around exporting an accessible mailbox/account. If you need to process multiple standalone OST files, a dedicated OST conversion tool can simplify the process.
Q7. Can I convert OST to PST in New Outlook?
A. New Outlook now supports several PST operations, including mailbox export, but its PST features differ from Classic Outlook. For the traditional Import/Export workflow, Classic Outlook remains relevant.
Q8. What is the easiest way to convert an inaccessible OST file to PST?
A. If the OST file is orphaned, corrupted, or inaccessible through Outlook, manual methods may not work. In such cases, Regain OST to PST Converter can be used to scan the OST file, preview available mailbox data, and export it to PST.
Q9. Is AutoArchive the same as converting OST to PST?
A. No. AutoArchive moves eligible Outlook items into a PST archive. It does not directly convert an existing standalone OST file into PST.













