I found an old PST file from years ago, and Outlook is asking for a password that I do not remember. It is my own file (not stolen or someone else’s), and I just need to recover the emails inside. I am using Windows 10 / Outlook 2016 (but the file might date back to Outlook 2007/2010). I have tried guessing a few likely passwords and checked old notes, but no luck. What is the safest and most reliable way to open or recover an old PST when the password is lost?