From AWinware Software:

Looking to protect your digital documents Adobe Acrobat PDF; Tryout pdf encryption software which helps to secure your bulk pdf files by applying open password on them. Software can be used to restrict pdf from printing, text copying, form filling, editing, signing and commenting etc. PDF password encryption software provides capability to encrypt data using 40 bits and 128 bits encryption level. Software ensures that the pdf file can only be opened by intended recipients i.e. only an authorize person can use the pdf. Software supports all windows based operating systems including Windows 7, Vista and XP. PDF password protection software is easy to use and affordable by all users. Tool is independent on another plug-ins and supports bulk pdf documents for encryption. Using this tool, both passwords user & owner can be set to protect your digital property.
Features:
# Software supports both 40 bits and 128 bits encryption security.
# Tool can be easily installed and run on latest windows including Win7 32bits and 64bits.
# PDF encryption tool process multiple documents in a single hit.
# Tool provides inbuilt help manual.
# Product is graphical user interface based and easy to use for all level of users.
# Tool preserves last setting used by software for future use.