From OST2PST Kit:
Microsoft OST to PST converter is an efficient email conversion tool from *OST files for Microsoft Exchange to *PST files for Microsoft Outlook. OST2PST Kit helps to convert OST to PST file of MS Outlook. Full compatibility of OST2PST converter with any version of Microsoft Windows and Outlook email client. Opens password-protected OST files. Converts OST files into various file formats: PST, EML, VCF, MSG and even TXT. Reads and converts corrupted *OST files. Opens encrypted OST files. Does not require Microsoft Exchange Server in order to function. Does not require Windows Domain Controller to open and read OST files. The Outlook OST to PST converter software can open Outlook files in OST format and convert the information into PST files.