You can try CubexSoft OST to PST Converter Tool to convert unlimited OST files to PST format with complete details and attachments. It is one of the programs to move batch OST data file to Outlook 2021, 2019, 2016, etc. This software supports multiple file formats such as PDF, MBOX, EML, MSG, DOC, RTF, TXT, Office 365, Gmail, Thunderbird, and many more. It was compatible with both Mac OS and Windows OS including Windows 11.
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