In order for the digital gauge to communicate with your computer using a USB port, drivers must be installed.   You will know if the drivers have not been installed when you plug in the digital gauge into your computer, run TECTITE and you see a message that says that the gauge is not communcating with TECTITE.   The driver file needs to be installed anytime you change computers. This driver is compatible the following versions of Windows: 7, 8, 8.1 and 10.