Microsoft doesn’t provide any option to open OST file in Outlook. However you can try the alternate solution. Actually you can import data in .pst file in Outlook. So you have to convert OST to PST format. For that you will need to download and install Advik OST to PST Converter from official website of Advik Software. 

With this software you can convert OST into PST format. After that import PST file in Outlook 2016, 2019 or 2021 version.

​Microsoft doesn’t provide any option to open OST file in Outlook. However you can try the alternate solution. Actually you can import data in .pst file in Outlook. So you have to convert OST to PST format. For that you will need to download and install Advik OST to PST Converter from official website of Advik Software. With this software you can convert OST into PST format. After that import PST file in Outlook 2016, 2019 or 2021 version.  Read More

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