Try OST File to PST Converter Tool
Download OST File Converter to PST Software to import all data from offline OST file to Outlook PST file with all email properties
Quick OST File Convert to PST Tool to read offline OST file and export all data from inaccessible .ost file to Outlook PST file format with all email properties. This software also migrate data or emails from the offline OST file into Exchange Server and Office 365 Mailbox. It recovers deleted items from OST file save them into readable file format.