To transfer data from OST to PST, you only need to get free OST2PST transfer software and for this. This OST transfer to PST tool will help you to free transfer OST to PST file without any error. This will provide the 100% result when you export Outlook data from OST to PST file. This software supports all the versions of MS Outlook like 2013, 2010, 2007, 2003 (32 bit & 64 bits) and also supports Windows OS like Windows 8.