Many users want to import OST file to Outlook.com, so here I suggest you download SysInspire OST to PST converter software. This tool converts OST files into multiple file formats for conversion such as OST to PST, EML, EMLX, Office 365, Yahoo Mail, Gmail, etc. It has technical support and all users get help by email or live chat. This tool has a demo version that converts 25 items from each folder of OST for free. It has PST file splitting users split PST files into multiple small sizes.
