An OL pst (pre OL2003 unicode format) at 1.5gb is perilously close to the
size at which problems can occur
If you still have access to OL on the old PC I would create a new archive
and move a substantial amount of data, then compact.
I would also run scanpst.exe on it, several times, before attempting the
copy process again
to hard drive then burned to CD. CD copied to my PC (XP home). Note when an
archive pst file was similarly transferred to another PC it opened, but the
'outlook.pst' primary file would not even copy (I/O error, 1.5GB pst file).
On my XP home PC both would copy but neither is recognized as a pst.