PDFKey Pro

PDFKey Pro is a lightweight and intuitive application that helps users recover files with lost or forgotten passwords and protect documents from unauthorized viewing by setting up passwords. As the name implies, it is only able to perform these operations for PDF files, so it doesn’t offer support for other file formats.

The GUI is really simplistic and offers quick access to the main functions of the program, namely locking or unlocking a PDF file. Adding files to the list proves to be extremely easy, as you can rely either on the “drag and drop” support or the browse button.

There are only a few configuration settings to tinker with, as you can make the program save the files to the same directory as the original documents or specify the destination, check for updates automatically, as well as append an unlocked or locked suffix at the end of the processed files' name.

In order to check out the content of the locked PDF file, the application creates a copy of the original one, which doesn’t require password identification.

When it comes to encryption options, you can select from two different profiles, namely basic or advanced security settings. The first one allows users to specify the password and pick the security level from a preset list, while the second offers the possibility to copy and print the documents even if they are protected with a password.

The application supports batch processing, which means you can add multiple files to the list and unlock or lock them simultaneously.

To sum things up, PDFKey Pro gives you a hand whenever you want to unlock or lock PDF files quickly and with minimum effort.