If manual method doesn't work and enable to split large pst then you can go with any paid software which can be easily available on internet but i personally recommend you this brilliant outlook pst splitter software which can easily split large PST file Outlook including emails, calendars, contacts, etc. It works efficiently and is capable of splitting large Outlook PST files into smaller one without any file size limitation.
It comes with a user-friendly interface and allows the users to effectively and efficiently split all the items from the Outlook data files. This can support all MS outlook version such as 2019, 2016, 2013, 2010, 2007 & 2003 and compatible with all Windows 10, 8.1, 8, 7.
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