Which OST to PST Method Fits You?
An OST file is the offline copy of a mailbox. A PST file is a portable data file, so OST to PST is the usual move to save mail. Microsoft notes that IMAP accounts use OST files in Outlook 2016 and Microsoft 365 too.
| Case | Method | Needs |
|---|---|---|
| OST opens in Outlook | Export wizard | Your Outlook profile |
| Few folders | Drag into a new PST | Your Outlook profile |
| Orphaned or corrupt OST | OST converter | The OST file only |
Can Outlook Convert OST to PST?
Method #1: Export Wizard (Free)
Who it suits. Users whose OST file still opens in Outlook. Extra application. None.
- Open Outlook with the profile that owns the OST file.
- Select File, then Open & Export, then Import/Export.
- Select Export to a file and Outlook Data File (.pst).
- Select the mailbox, tick the subfolders option and set the file name.
- Select Finish and add a password if you want one.
Microsoft describes both file types in its data files overview.
Profile rule. An OST file works with the profile that created it. Convert it on the PC where the account was set up.
Can You Copy OST Folders Into a PST?
Method #2: Drag Into a New PST (Free)
Who it suits. Users who need only a few folders. Extra application. None.
- Select New Items, then More Items, then Outlook Data File.
- Name the new PST file and select OK.
- Drag the folders you need from the mailbox into the new data file.
- Close the data file and copy the PST to your drive.
Both manual methods need an OST file that opens. They fail for an orphaned or corrupt file.
How do You Convert an Orphaned OST?
Method #3: OST Converter (Paid After Demo)
Who it suits. Users with an orphaned, corrupt or inaccessible OST file. Extra application. OST Converter.
OST Converter reads the OST file directly and exports to PST and 15 other formats. The software needs no Exchange connection. The vendor page lists a deep scan for damaged files.
- Start the software and select Add File.
- Select the OST file and wait for the scan.
- Preview the folders and items.
- Select PST as the format and set the filters.
- Choose the destination folder and select Export.
The free version converts 25 items per folder.
Want the product details? Read the OST Extractor review.
What should You Check After the Conversion?
- Open the PST file in Outlook and compare the folder counts after the OST to PST export.
- Check that the calendar and contacts folders came across.
- Copy the PST to a second drive.
- Do not delete the OST file until the check ends.
Need PDFs instead? See how to export OST to PDF.
Seeing a rising OST size? Read the OST size error fix.
Frequently Asked Questions
What is the Manual Way to Get an OST to PST Result?
Open the OST profile in Outlook and use File, Open and Export, Import/Export, then export to an Outlook Data File.
Can You Open an OST File on Another PC?
Not directly. An OST file works with the profile that created it, so convert it on the original PC.
What if the OST File is Corrupt?
Use an OST converter. The converter reads the file directly and does not need the original profile.
Does OST Converter Need an Exchange Connection?
No. The vendor page states that it needs no Exchange connection.
What does the Free Version of OST Converter Export?
The free version converts 25 items per folder.
Which Accounts Use OST Files?
Exchange and Microsoft 365 accounts use them. Microsoft notes that IMAP accounts use OST files in Outlook 2016 and Microsoft 365 too.
Does the PST Include Calendars and Contacts?
Yes. The export wizard and the converter both include calendar and contacts folders.
Author's Verdict
Use the export wizard when the OST file opens in Outlook.
Use an OST converter for orphaned or corrupt files.
Key Takeaways
- OST files belong to one Outlook profile.
- The wizard fails for damaged files.
- OST Converter reads the file with no Exchange link.
Related Guides
Moving mail to Gmail instead? See how to import an OST file to Gmail.