Having PDF files and need to protect your content against unauthorized users? Lock PDF is one the most suitable solution to lock PDF files & lock PDF documents. Lock PDF is one of the most reputed utility to Lock PDF from copying, lock pdf from editing, lock pdf from printing etc. With Lock PDF program users can quickly apply PDF restrictions & set PDF permissions. Now lock pdf files & lock pdf documents in just 4-5 seconds using competent PDF Lock program. Lock PDF program enable users to apply 2 security settings: 1) Add Password to PDF Document - To add user password to PDF files. 2) Add Restrictions to PDF Documents - To apply restrictions like: copy, edit, print on PDF files. The program successfully lock pdf files of Acrobat version up to 9. Use Lock PDF program to protect pdf, secure pdf, restrict pdf etc. The program to lock PDF files & lock PDF documents successfully runs on Windows 98, ME, NT, 2000, XP, 2003, Vista, 7 systems.