If you want to import OST file to Outlook.com without losing any important data. So use the SysInspire OST to PST converter software where you can easily convert or import OST files to Outlook.com and a lot of other email client applications without losing any important data. It supports all version applications of Outlook and is capable to run on all windows operating systems without facing any problems. To get more about this tool try the free demo version without any payment.
Know more:- Import OST file to Outlook.com