From Thegrideon Software:
Outlook Password by Thegrideon Software is advanced MS Outlook password recovery tool.
It instantly recovers MS Outlook .pst (Personal Storage, Personal Folders) files passwords as well as e-mail account's passwords and settings stored in MS Outlook records. Fully Compatible with Windows 10.
All MS Outlook versions and encryption methods are supported (including x64 editions).
Large .pst files (4Gb and larger) are supported.
Outlook Password lists current MS Outlook Profiles and associated .pst files.
.pst file search and mass processing feature is available.
What's new in this version:
Version 2016.04.05: SHA-256 signed. Microsoft Outlook 2016 fixes.
I had a 200mb Outlook 97 PST file that somehow got a password on it. Don't know how, but I needed the e-mails back! For $19, this program worked perfectly AND was the cheepest password recovery software out there. Very good!