Kleopatra - Kleopatra is a certificate manager and GUI for GnuPG.
Folder Lock - Folder Lock is a security software that helps you to password protect files, shred files, clean history, encrypt the personal documents and much more.
KeePassXC - KeePass Cross-Platform Community Edition - A community maintained fork of the popular KeePassX...
Windows BitLocker - This topic provides a high-level overview of BitLocker, including a list of system requirements, practical applications, and deprecated features.
KeePass - KeePass is an open source password manager. Passwords can be stored in highly-encrypted databases, which can be unlocked with one master password or key file.
My Lockbox - My Lockbox is a security software enabling you to password protect any folder on your computer.