As you might already know importing OST files to Outlook isn’t possible as Outlook doesn’t provide any option to import these files. However, if you are looking for some ways to add an OST file in Outlook, then don’t worry, we have got a way around for you.

This article will provide easy and quick ways to import OST files in Outlook 2021, 2019, 2016, and 2013. But before that, you need to understand that the OST file can be found in two states – a connected OST file and an orphaned OST file.

What are OST Files?

Microsoft Outlook generates the OST file upon configuration with an Exchange Server. It serves as a local repository for storing mailbox data on your system. Furthermore, if we dig deep into the state of OST files, there are generally two states – a connected OST and an orphaned OST.

The difference between both these states is if the OST file is connected to its respective email account and can be accessed in Outlook, then it will be considered as a connected OST file. Or we can say that the OST file is in a connected state.

However, if the OST file is not connected to its respective email account, then it will be called an orphan OST file. For eg: You copied your OST file from System 1 and pasted it into System 2. Then in System 2, that OST file is not connected to its respective account anymore and is now an orphan OST file.

Now if you are thinking what is the point of learning so much about OST files when you just want to import OST files in Outlook? Then you must understand that the process that you choose for importing these files differs depending on the state of the OST file.

How to Import OST Files in Outlook for Free

If you are planning to opt for a free method to add OST into Outlook, then you must know that you can only do this with a connected OST file. Yes! You heard it right. You can choose this option only if you have an OST file connected to its respective email account and is accessible in Microsoft Outlook.

Now let’s find out the solution to perform the import process.

You might already know that Outlook does not provide any direct method to open OST file in Outlook. So, the first process involves converting the OST into PST file. Following that, you can import that resultant file in Outlook.

You can export the data in PST file using the Import/Export Wizard as shown below:

1. Open Microsoft Outlook and go to File > Open & Export > Import/Export.

2. Select the Export to a file option under this wizard.

3. Choose Outlook Data File (.pst) option from this screen.

4. Select the folder or profile that you want to export.

5. Finally, choose the storage location to save OST file data and click on the Finish button.

This step will get you a PST file that you can now import in any Outlook using the same Import/Export wizard.

Perfect Way to Import OST Files in Outlook (Orphan or Connected OST)

In case you have an orphan OST file or you don’t feel confident using the manual procedure to add OST into Outlook, then the perfect option that you can choose is Stellar OST Converter. This amazing solution will help you load an orphan, damaged, or encrypted OST file into the tool and convert it into PST format.

One of the best features of this tool is that you don’t need to have an Exchange Server environment to run this utility. Furthermore, you can also convert mailbox items like emails, contacts, calendars, notes, tasks, etc. while ensuring 100% data integrity.

How you can Use this Tool to Open OST into Outlook via PST?

Step 1. Download this software and install it on your system.

Step 2. You can either choose the Profile List option if you want to import the connected OST file. Else, you can manually select the OST file if it is an orphan OST.

Step 3. After selecting the OST file, click on the Convert button to proceed further.

Step 4. Now click on Save Converted File option present under the Home tab. Then choose PST as your export option and click on the Next button.

Step 5. Then browse the storage path and enable the Recover Deleted Items and Auto split PST checkbox if required.

Step 6. Finally, apply additional filters depending on your choice and start converting the data into PST format.

Step 7. Once you get the resultant PST file, you can import that file in Outlook using the Import/Export wizard.


If you are looking for a reliable and trustworthy solution to import OST into Outlook, then this is the article that answers your query. Although we have mentioned both manual and automated procedures to add OST files, you need to understand which process better suits your requirements.

Frequently Asked Questions

Q1. How can I open OST file in Outlook?

A. You can either use the Import/Export wizard or the third-party tool by Stellar to add OST into Outlook 2021, 2019, 2016, 2013, or previous versions.

Q2. Is it necessary to use this tool if I want to import orphan OST file in Outlook?

A. Yes, if you have an orphan OST file, then you don’t have any option other than a third-party utility as Outlook doesn’t directly import OST files.

Q3. Is there any option to import a corrupted OST file into Microsoft Outlook?

A. Yes, you can simply use the software mentioned in the above section in case you have a corrupted OST file. The software by Stellar supports conversion of orphan, damaged, and encrypted OST files.

Q4. I have copied an OST file from another system and now I want to import it in my Outlook. Which method will be suitable for me?

A. In your case, the OST file on your system is orphan and cannot be opened using the free manual procedure. So, you can use the aforementioned software to open OST file in Outlook.

By Mark Weins

After completing my graduation in Computer Science, I entered the technical world to explore my passion for technicalities. After working for over 7 years in this industry now, I have received over 10 awards as a tech expert.