PST is the most important and
core component of Outlook, responsible for storing all the data items, such as
messages along with attachments, contacts, notes, journals, etc. This long list
of items just increases and so does PST file. Outlook PST file size is the
biggest concern as it is susceptible to get corrupt when reaches or goes beyond
its size limit. Microsoft has defined default size limits for PST in different
Outlook versions. In earlier versions of Outlook, such as Outlook 2002 and
older versions, offer a PST file of 2 GB limit.