What are some alternatives?
When comparing Protect Folder and Ruler, you can also consider the following products
Vov Hide Files - Lock your files and folders from prying eyes.
MailHog - MailHog is an email testing tool inspired by MailCatcher, but easier to install.
Wise Folder Hider - Wise Folder Hider is a free file/folder hiding tool.
Printix - Printix is a cloud-based print management platform.
Lock a Folder - Lock a folder, file or even removable drives to make them inaccessible from both local and remote users. Once your personal files and folder are protected cannot be seen, read or modified in any manner without your permissions
PrinterLogic - PrinterLogic is an enterprise print management software.