I found this video from adobe how to protect your document. I am using latest Adobe Acrobat Reader 9. Note I am trying to put password inside the reader itself. If I go to
File > properties > security
everything is simply disabled. If I go to
help > plugins
There is a plugin for security but I can't seem to find it or install it to put that feature in. Does anyone know regarding Adobe Acrobat Reader only. If it can't be achieved with Reader alone, than other help will be appreciated.