Download the latest and official version of drivers for HP Photosmart A646 Compact Photo Printer. This driver package is available for 32 and 64 bit PCs. It is compatible with the following operating Systems: Windows 8.1 (32-bit), Windows 8.1 (64-bit), Windows 8 (32-bit), Windows 8 (64-bit), Windows 7 (32-bit), Windows 7 (64-bit), Windows Vista (32-bit), Windows Vista (64-bit), Windows XP (32-bit), Windows XP (64-bit). Don't worry if you don't know what's your operating system. HP website will automatically detect your device and select the best installer for your OS.