Passware works
I don’t remember why I did it, but 16 years ago I password-protected that year’s email. In practical terms, I used Outlook to set a password on the PST-file. I haven’t looked at the emails of 2001 since, but for mundane reasons I needed access to them now. But how to remember a password set 16 years ago?
The encryption is horrendously poor. It is a mystery that Microsoft could implement a solution of such low quality at that time; I was running the latest Outlook and we are not talking 1968 here! I studied the PST file format I decided that while it was doable to write a parser and do a key-search, the effort would require more time than what I have available. My 2001-emails are not that high on the list.
Google turns up passware. I don’t run software that I pull out of the air like this. So I enable Hyper-V in non-networking mode and, after having forked out US$79, I run it. I can’t vouch for claims they make on other file types, but on non-ANSI PST-files, passware works.
For the technically inclined: I did not set the password 006422335075. It is, however, the first found of many, many that hashes to the same value. Utterly poor engineering, and eternal shame on Microsoft.