AxCrypt is a free, easy to use and open source file encryption tool for Windows 2008, Vista, 7, 8 and 10 integrated into Windows Explorer. Encrypt, compress, decrypt, wipe, view and edit with a few mouse clicks. Cryptographic primitives are AES-128 and SHA-1. No configuration is necessary for AxCrypt just download it, run the installer and it's ready to go.
Thanks to SalaR for the update.