An OST – an Outlook data file – is replica of your Microsoft Exchange, IMAP, or Microsoft 365 mailbox server data. It allows you to work offline and automatically synchronize changes when connected to the server. While, a PST file is used to store your entire mailbox data locally. It is mostly used for backup, migration, or archiving purposes.
However, sometimes you need to convert OST to PST in scenarios like:
- When an Exchange server account becomes inaccessible or is deleted.
- During migration from one Outlook profile or system to another.
- For creating secure backups of emails, contacts, calendars, and attachments.
- To recover data from orphaned or corrupted OST files.
Since OST to PST conversion can cause data loss if not done properly, so it should be done carefully. This post outlines the safe methods to convert OST file to PST.
How to Convert OST file to PST Safely?
Below we have listed the reliable and safe methods to convert OST file to PST:
- Using Outlook Import/Export Wizard
It is one of the easiest and most effective ways to convert an OST file to PST format is to use the Import/Export wizard of Outlook. This built-in feature allows you to export your mailbox items like contacts, calendar, emails, and others. See the following for the steps:
- Launch Outlook on your computer.
- Go to File tab and click on the option Open & Export.
- Choose the Import/Export
- Click the option – Export to a File.
- Click on Next.
- Now, choose Outlook Data File (.pst).
- Click Next.
- Choose the mailbox folders you want to convert to PST.
- Make sure to check the Include subfolders box.
- Click Next.
- Enter a name for your PST and choose a save location.
- Click Finish.
- Using Outlook Archive Feature
You can also use Outlook’s Archive feature to convert OST file to PST. This feature is mainly used for old mail data into a PST file. Below are steps to export your OST data into PST format using this method:
- Go to File
- Click on Tools> Cleanup Old Items.
- Choose Archive this folder and all subfolders
- Then choose the folders you want to convert to PST.
- Set the archive date—any emails or items older than this (e.g., 19/2/2026) will be moved to the PST file.
- Select a location for the archive PST.
- Click
- Now, Outlook will create a PST that contains all the mailbox items older than the selected date.
- Drag and Drop Methods
This is another method you can use for converting OST file to PST. By using this method, you can manually copy and move only selected mailbox data from the OST file into a new PST file. This allows you to back up only the items you need while still creating a portable, easily accessible PST for future use.
- Go to the Home
- Select New Items > More Items
- Choose on Outlook Data File, it will create a new PST file.
- Enter the name of PST file (e.g., Backup _PC.pst).
- You will see this file in your folder pane as a new mailbox.
- Now you can drag and drop the required folders.
- Close Outlook after all the required data is moved to the new PST and find and check the PST file.
4. Using a Professional OST to PST Converter Tool
OST to PST conversion methods that are mentioned above are only useful when your Outlook profile is accessible. If your Outlook is not working or the OST file is orphaned, you cannot rely on these manual methods. when such things happen, a professional software like Stellar Converter for OST becomes a great option as it provides a secure and efficient approach to convert OST to PST. The tool handles oversized and not accessible OST files, maintains the original folder structure and offers you the possibility to save files in various formats like MSG, EML, RTF, HTML, and PDF. Check out the instructions below to get the most out of this software:
- Visit the official website of Stellar Converter for OST.
- Download and Install the application.
- Launch the software.
- Now there are two options will display: List Profiles and Choose Manually.
- Select List Profiles.
- This will automatically list your OST file.
- Select the OST file and click on Convert.
- All your mailbox items are listed in three pane preview after conversion process is complete.
- Now click on Save converted file tab.
- Choose the PST file format then save your PST in desired location.
Conclusion
In this article, we have mentioned step-by-step process to convert the OST file to PST safely. Converting OST to PST is crucial to make sure that your mailbox data, stays, safe, accessible, and recoverable in any case. You can use the methods highlighted above to convert the OST file to PST. However, if your OST file is orphaned, inaccessible, or corrupted, then you must go for a professional OST converter tool. Stellar Converter for OST is one such tool that can convert your orphaned or corrupted OST file to PST and recover all your mailbox items.
