Do you want to import OST file into Outlook 365 step-by-step guide? here I advise you to download eSoftTools OST to PST Converter software for access all data of Outlook OST files. This tool export OST files into Windows 10 and also multiple file formats such as OST to PST, EML, EMLX, Office 365, Yahoo Mail, Gmail, MSG, MBOX, etc. It supports all versions of Windows OS. This tool does not require installing MS Outlook in users' PCs to open an OST file. It has bulk conversion users can convert OST files in bulk at the same time.