Oversize PST files are often a cause of PST file corruption. If the data in the PST becomes larger than its exceeding limit then it corrupt the PST fille. To avoid file corruption and Split PST file we can manually reduce its size by Clean Up utility.

Select the Clean Up tool from MS outlook and then choose Archive Option
Then Select Archive this folder and sub folders
Select data from mailbox to move
save the new .pst file to a new folder
If you would like to get the process going then go here: mergeoutlookpst.com/split-outlook-pst