To get the latest drivers for your OS, visit the serial chipset's manufacturer's web page at:

http://www.silabs.com/products/mcu/pages/usbtouartbridgevcpdrivers.aspx

For linux, for the rucosmic software, you do not need to download a driver.

For windows, plug in the USB cable and powered on quarknet board, while watching COM PORTS using Device Manager. If a COM port is not created when you plug in the cable, then install the driver using the above link. Use the driver WITHOUT Serial Enumeration (use the Default driver).