HP Envy 7640 Reset
Power up the HP Envy 7640 printer if it is turned off previously. Wait until the printer becomes idle. Disconnect the power cable from the HP Envy printer and power supply. Wait for a few minutes. Link the cable to the respective port of the printer and electrical outlet. Do not make the connection using a surge protector as it may produce power fluctuations. Now the printer turns on automatically. If the HP Envy 7640 Setup printer does not power up, switch it on by force pressing its power button.