If you have an OST file and you want to Convert OST to PST then you may try the eSoftTools OST to PST Converter software. Users can convert the OST file to PST formats for free. Everyone can operate this software in any version of Windows like 8, 7, 10, XP, etc. and this will offer you a free demo version and you can use the free demo versions from the official websites of eSoftTools. You can download this software from the official websites of eSoftTools.

Know more -https://www.esofttools.com/blog/free-unlimited-ost-to-pst-converter/