Nothing is exposed in the object model. Reading the file size using FSO or
the Win32 API's or whatever is the best way to get overall size of a PST
file.
Thanks for your reply.
Cause the particularity of PST file. If divide the pst file in outlook, the
file size of the old pst file is same as before dividing except compress
manually.
So the file size may not be the actual size.
The file size is the size, it also includes any "whitespace" that's there
until you do compress it. If you want the size of the actual folders in the
PST file that's a different story. In that case you'd have to do something
like counting every message in a folder and getting each one's size and then
realizing that there are also hidden items in folders plus folders that
aren't visible to you in the UI that also make up part of the size of a PST
file.