You can also try OST2PST Wizard if you want to convert OST file into PST format. It can maintain the same data as well as preserve the meta properties of the OST file during the conversion. It will definitely repair your OST file without losing any information. There is an available free download version of OST to PST converter to convert upto 25 items. It can show the capability of OST2PST Wizard.

Free Download Source: https://www.ost2pstwizard.com/?

Download the user-friendly OST to PST Converter to repair and restore the corrupt OST file. It is the best utility to recover the OST file and it can be used by anyone. OST to PST Converter can easily recover OST file and convert into PST file. It can be used for any Outlook versions to recover OST file. At the time of OST file conversion, the user is not required for the installation of MS Outlook. 

Read more info: https://www.ost2pstwizard.com/

Try Outlook.com backup tool ?to get the complete solution for backup issues related to Outlook.com.

If you are unable to repair OST file then, I would like to suggest you can try the OST2PST Wizard. It can migrate all OST data into PST file format without losing any file. OST to PST Converter is helping to easily recover OST data items such as emails, contacts, notes, tasks, journals, etc. 

For further info: Migrate OST to PST file