Axantum's AxCrypt (64-bit) is a powerful encryption utility for 64-bit editions of Windows. It not only encrypts and decrypts files but also adds file renaming, password protection, key-file generation, and secure delete. AxCrypt integrates with Explorer, so you only need to right-click a file and select AxCrypt from the file's context menu. Better still, it's freeware.
Since AxCrypt runs automatically with Windows and integrates with Explorer, there's no separate program interface, though a Start Menu folder offers links to documentation and registration pages as well as an uninstallation utility. We right-clicked a random folder and selected the AxCrypt menu, which offered three types of encryption: Encrypt, Encrypt to Copy, and Encrypt to Exe. We could also select Decrypt, Rename, Shred and Delete, and either Clear the Passphrase Memory or Make Key-File. We selected Encrypt to Copy, which called up a small dialog containing fields for entering and verifying our passphrase or a key file as well as check boxes to save the entry for decryption or to use it as the default for encryption. We entered our passphrase and saved the encrypted copy in the program's .axx file format. AxCrypt copied icons for each secured file on our desktop. Clicking any of these opened a text file, but right-clicking an encrypted file let us open it either by entering the passphrase or by just clicking Decrypt with the passphrase memory feature selected. Next we tried the Key-File tool, which advised us only to save our key file on removable media, to print a backup and store it securely, and to never encrypt the key file itself: all wise precautions. Key File encryption is much stronger than passphrase encryption, and encrypted files can't be recovered if you lose the key file. The Shred and Delete tool "shreds" each file individually as it's deleted to make it unrecoverable. AxCrypt even offers a choice of a dozen European languages.
Having AxCrypt right there when you right-click makes it especially useful as well as easy to use. Indeed, it's hard to image how it could be made easier to use and still be able to securely encrypt and decrypt sensitive data.