NirSoft PST Password is a tool that instantly recovers your lost Microsoft Outlook PST password.
A unique feature of the form of encryption Microsoft Outlook uses for PST files is that each password-protected PST file has more than one viable password.
This utility can recover the PST passwords of Outlook 97, Outlook 2000, Outlook XP, Outlook 2003, and Outlook 2007. You don’t have to install MS-Outlook in order to use this utility. You only need the original PST file that you locked with a password.
Note that the program will automatically find any PST files stored in the current user profile under
Document and SettingsUserLocal SettingsApplication DataMicrosoftOutlook
If you want a different PST file, just drag it into the window or press F7 to browse for the file.