Windows has a built in encryption scheme known as EFS. You can put the "encrypt" and "decrypt" entries in the context menu and then encrypting a file is only two clicks away.

1. navigate registry hives
• HKLM
• SOFTWARE
• Microsoft
• Windows
• CurrentVersion
• Explorer
• Advanced
2. change the following key
• data name: Encryption Context Menu
• data type: REG_DWORD
• data value: 0 or 2 (see below)

  0 = disable

  1 = enable