There is always this password, this pdf, being secured by you. In fact too secured that you can never remember the password. Instead of move the PDF to trash there some way to recover the password.
There are a bunch of PDF password recovery/cracking software charging a few to tens of dollars. While in the wonderful work of Unix/Linux you, this kind of tool is free. There is one that I found recently:
To install, on Ubuntu
sudo apt-get install pdfcrack
on OS X, install brew and:
brew install pdfcrack
You will be prompt to enter password to install the tool
To start the recovery, simply:
To save use control-C to exit the tool, the tool will attempt to save.
The recovery process may takes hours to days depends on the security setting of the PDF. You will be prompted with the recovered password in command prompt upon succeed.
Let me know if it saved your day 🙂
* Be sure you have the right to perform recovery, i.e. you own the file but forget the password. Any wrong doing will still be wrong doing, so don’t do it.
* For Windows users, make friend with unix/linux people. They are like dentists, scary but really helpful.
pdfcrack [Official link]