Try Online Version : http://onlinepdfapps.com/protect-pdf/
With Free PDF Protector 4dots you can batch password protect pdf files.It is absolutely free, very easy to use and also multilingual. You can batch add password to pdf, both a user password (used for opening the PDF documents) and an owner password (used for settings various permissions such as content copying, commenting,printing, form field fill-in). Whole folders with PDF documents and their subfolders can be selected to be protected. Drag and drop.
What's New in Version 4.4:
New feature : Specify new user password and new owner password for each PDF document.
New feature : Import CSV with existing user password, new user password, new owner password.
What's New in Version 4.2:
Fixed bug : Protecting did not work correctly.
Fixed bug : Command line usage did not work correctly.
What's New in Version 4.0:
Fixed bug : Works now with large files (over 250MB) under Windows 64bit.
What's New in Version 3.1:
Keep folder structure
Import List from file with various encodings.
Fixed bug : File can now be opened with the "Open With" context menu option of Windows Explorer.
With Free PDF Protector 4dots you can batch password protect pdf files.
It is absolutely free, very easy to use and also multilingual.
You can batch add password to pdf, both a user password (used for opening the PDF documents) and an owner password (used for settings various permissions such as content copying, commenting, printing, form field fill-in e.t.c.).
Whole folders with PDF documents and their subfolders can be protected.
You can batch password protect pdf documents with 128 bits or 40 bits encryption passwords.
You can password protect pdf files simply with a right click in Windows Explorer since Free PDF Protector 4dots can be integrated into Windows Explorer.
Also, you can just drag and drop PDF documents to be protected to the main window of the application.
A text list file of PDF documents can be imported.
The application does NOT need Adobe Acrobat software installed.
With Free PDF Protector 4dots you can also batch set metadata of PDF documents such as author, subject, title, keywords, creation date e.t.c.
It can also be executed from the command line, which is useful for inclusion in scripts.
The application is multilingual and translated into 38 languages.