HP Envy 7640 touchscreen issue occurs when you turn ON the HP Envy 7640 Printer and the operation panel of the device does not work. Try resetting your printer by following the procedures mentioned.

Step 1: Turn ON your HP printer.
Step 2: Wait until the printer remains silent and idle before you proceed.
Step 3: Interrupt the power connection of the printer by removing the power cord from the back of it.
Step 4: If the printer uses a wireless or network connection, let it stay connected to the Internet.
Step 5: Open the cartridge access door and remove the ink cartridge from the respective slot.
Step 6: Turn ON the printer and unplug the power cord from the rear of the printer and also from the power outlet.
Step 7: Reinsert one end of the cable to the rear of the printer.

Step 8: Plug the other end to the electrical socket.
Step 9: Make sure you do not connect to the surge protector or film strip since the printer might not receive enough power to function properly.
Step 10: Turn ON the printer by using the Power button.
Step 11: The printer might undergo a warm-up period.
Step 12: The printer lights start blinking, and the carriage might start moving.
Step 13: Wait until the warm-up period completes and ensure your printer does not make any noise.
Step 14: Reinsert the cartridges into the correct slots.
Step 15: Close the cartridge access door.
Step 16: Print a calibration page, if prompted. Insert the USB cable into the printer and the computer (if disconnected).
Step 17: Try to print and check if the touchscreen works. If the panel still does not work, update the firmware.
Step 18: The firmware can be updated directly from the printer or through the website.

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