VeraCrypt - VeraCrypt is a free open source disk encryption software for Windows, Mac OSX and Linux.
Wise Folder Hider - Wise Folder Hider is a free file/folder hiding tool.
Easy Vault - Easy Vault: Hide Pictures, Videos, Gallery, Files is an all-in-one privacy protection application designed for those who want to lock and hide their private files.
Vov Hide Files - Lock your files and folders from prying eyes.
Gilisoft File Lock Pro - Password Protect Files, Folders on Local Drive , USB drive or LAN Network.
Windows BitLocker - This topic provides a high-level overview of BitLocker, including a list of system requirements, practical applications, and deprecated features.