Download the free demo version available of vMail OST to PST Converter software and you can save 30 emails in each folder above each file format. This is the best third party tool in the market. It is very easy to use and quickly recover all corrupted offline OST file. In this Software have many features. It supports all versions of MS Outlook. It has provided export data in Cloud App office 365 & live exchange, required only login details and you can access your data anywhere.
Get more info- https://www.vsoftware.org/blog/how-to-split-ost-file.html
Get more info- https://www.vsoftware.org/blog/how-to-split-ost-file.html