You can set the Security Properties of a PDF file in Adobe Acrobat, as mentioned in my post in your other thread. There are separate Acrobat Macintosh and Acrobat Windows forums.
However, be advised that there are commercial programs legally available that can take any supposedly protected PDF and generate an exact, unprotected clone of the document in a matter of seconds. I use PDFkeyPro myself on my Macs, mainly to circumvent editing "protection" in things like multilingual user manuals, where one version is enough so the others can be discarded, and to edit the Chinglish and Japenglish gibberish on such documents to make them understandable.
The "protection" touted by Adobe is completely illusory.
Hi Tai Lao ,
actually i'm using acrobat reader version 9.0 where there is an option document>security,security setting options.But if i go through them also i'm not able to set a password to pdf document...
to be in brief,
in Document -> security option
Show security properties
Import security settings
in Document -> security settings option
a security setting dialog will open saying about digital signatures..
exactly which one should i need to use in order to set a password to my pdf document.May b i'm asking a silly question but ur answer wil really help me...
I agree that, you can use Adobe Acrobat or other PDF editor to add open password or user password on your PDF files. But these ways would be helpless to protect the security of your PDF files. Because there are many free or charge PDF Password Remover or Reconvery can easily rip the restrications. It is sometimes illegal but....you know, this is the truth.