Windows 7 Home Premium does not include file level encryption. This is limited to the more expensive (Professional and up) versions of Windows 7. While there are a number of freeware file encryption programs, I wanted one that worked as an Explorer extension for convenience and had both 32-bit and 64-bit versions. After looking around a bit, I discovered that Windows 7 and 64-bit support was still fairly rare. Fortunately, one of the better file encryption program, AxCrypt, had a beta version with Windows 7 and 64-bit support.