If you find How to Export OST file into many workable file format? So you can try
Software can repair damaged OST File without facing any data loss. The tool helps to extract data from corrupt OST file and creates a new PST for all mailbox data. Recover OST File items easily save in multiple files formats i.e. PST,
EML and DBX formats respectively.
You can FREE download OST to PST Conversion tool: