After connecting the HP Printer with your PC, the error message of ‘Device Setup failed’ or ‘Unknown device’ is visible on the screen after installation. This issue can arise due to many reasons like USB cable, malwares, and viruses etc. So as to resolve this issue users need to perform following troubleshooting steps:

 Reconnect the USB cable properly with your printer and PC
 Make sure the USB cable is not faulty or damaged
 Try connecting the USB cable on other ports like if you are connecting it on the back side of the PC then try to connect it in the port given in front
 Reset your printer and then begin the installation of the printer
 Get help from technical representative via HP Printer customer support number which stays put at all hours.