It works by removing passwords that restrict access in two areas. One is for passwords that restrict some functions such as printing copying and pasting. The second is any password that might prevent you from accessing or opening a PDF file.
To remove the first type of restrictions, just drag your PDF file onto a link on your desktop or alternatively onto the Free PDF Unlocker icon on your desktop. Instantly, Free PDF Unlocker should remove the password and allow printing or copying & pasting the contents from the PDF File.
To unlock the second kind of restriction with Free PDF Unlocker, you have to right click and select "Remove PDF Password" and close the application. The former function seems to work most of the time but the latter would not remove the password in my case. If you are having problems, you can leave a comment on the developer's blog.
Free PDF Unlocker can help you access and edit those protected PDF files that you've been unable to access up until now but don't bank on it.
Click Here to Download Free PDF Unlocker