The automated software to split big PST file into smaller parts is SysInspire PST Converter. They Convert large PST files into smaller parts without any stoppage, it has a no size limitation feature. The live preview of PST conversion is also shown in this software on which you can able to see every item of Mailbox. To use this software you no need to install an MS Outlook on your pc. This is a purely secure and 100% virus-free software and you can also try the free demo version of this software.