PDF Unlock & Lock is a straightforward piece of software that gives you the possibility to seamlessly add password protection to PDF documents, as well as to remove it. It features intuitive and clear-cut options that can be figured out even by inexperienced users.

After a fast and uneventful installation operation, you are welcomed by a user-friendly interface, where the main window displays two large buttons for locking and unlocking PDFs, respectively.

Worth noting is the fact that it doesn't lock the original files but creates new, password-protected ones instead. This may be considered a backup method, since you can reuse the original files if you happen to change your mind. Just remember to not leave them lying around for other PC users to find. The same rule applies to unlocking files too.

It's possible to restrict access to multiple PDF docs at the same time, thanks to the fact that the application offers batch processing support. The task list reveals the full path, size and status of each file.

All you have to do is indicate an output destination for the locked docs, as well as to enter and confirm two different passwords, one for viewing access and the other for printing, copying and editing permissions.

Unlocking the keys can be done by following the same steps: add the PDFs to the task list, specify the output directory for recreating the original files, as well as enter and confirm the two correct keys.

There no stability issues in our tests, thanks to the fact that the program didn't hang, crash or prompt error messages. It carried out tasks rapidly while remaining light on system resources consumption.

Although it doesn't come loaded with richer options and customization preferences, PDF Unlock & Lock provides you with a simple and effective solution for locking and unlocking PDF files, and it can be easily used by anyone.