RE: Touch Screen has stopped working on Dell Inspiron 15R-5537
"Currently, this hardware device is not connected to the computer. (Code45)To fix this problem, reconnect this hardware device to the computer."
If none of the troubleshooting steps fix the touchscreen, I suggest you reseat the touch screen / display cable. Note: Please do this step only if you're comfortable in opening the computer. Read the owner's manual thoroughly before attempting this step.