A PST is the data file used to store all your messages, calendar events, and other items in Microsoft Outlook and other Microsoft software.
PST store the 32 bit CRC32 hash value of the password entered by the user. When a PST file is opened using any version of Outlook it’ll check the hash value stored in it.
The problem with CRC32 hash is the fact that a lot of strings can have the same CRC32 hash.This means for a single 32 bit hash value there will be a lot of different but correct passwords!
PST Password Recovery tools are user friendly graphical interface and equipped with safe algorithms. All the techniques are safe and non-destructive to marintain complete data integrity.
I can refer you a link which can help you to recover lost PST password efficiently.
SysInfoTools PST Password Recovery Software is the best utility to recover lost PST file password.
It can recover PST Password for files created with Outlook 2007, 2003, 2002 and 2000. It is compatible with Windows Vista, XP, 2003 and 2000.
*www.sysinfotools.com/recovery/outlook-password-recovery.html