For Converting OST file to PST file you can take help of this OST to PST Converter Software that Convert OST file to PST file and give you option to save them into multiple file format like: PST, EML, MSG, MBOX, HTML, ICS, VCARD formats. This software is world famous utility which provide 100% accurate result after recovery process and convert the entire data into pst along with email, inbox, outboxes, sent-items, deleted-items, drafts, contacts, calendars, notes (To, Cc, Bcc, Subject, Date and Time). It supports all the version of MS Outlook up to 2019. You can also migrate the OST files into Office 365 & Live Exchange Server
Checkout it free demo version which to discover features and function before purchasing the full licensed version. this trial version will see you preview of recovered or converted OST emails.
OST to PST Conversion tool has many unique features that make it an exclusive product among other application. This application supports 98, 2000, 2002, 2003, 2007, 2010, 2013 2016 and 2019. Before converting Your OST data into Outlook PST file format you can see the preview of recovered mailbox item and after that, you can save the result into PST, MBOX, MSG, EMLX, HTML, PDF, Office 365 file format.