The touch screen on my Envy 7640 does not respond to touch.

[tmiller001]

My HP Envy 7640  is not allowing me to choose to print or scan from the touch screen.  It appears to be locked and does not respond to the touch.

[Echo_Lake]

@tmiller001

Thank you for posting on HP Support Community.

Don't worry as I'll be glad to help, I have a few troubleshooting steps we could try to fix the issue:  

I suggest we reset the printer using the below steps:

• Turn on the printer.
• Wait until the printer is idle and silent before you continue.
• Disconnect the USB cable from the rear of the printer. If your printer has a network or wireless connection, leave it connected.
• Remove the ink cartridges from the printer.
• With the printer turned on, disconnect the power cord from the rear of the printer and from the wall outlet or power strip.
• Wait at least 60 seconds.
• Plug the power cord back into the wall outlet.
  •  NOTE:HP recommends connecting the printer power cord directly to a wall outlet.
• Reconnect the power cord to the rear of the printer.
• Turn on the printer, if it does not automatically turn on.
• The printer might go through a warm-up period. The printer lights might flash, and the carriage might move.
• Wait until the warm-up period finishes and your printer is idle and silent before you proceed.
• Reinsert the ink cartridges, and then close the ink cartridge access door.
• If you receive a prompt to print a calibration page, do so.
• If you disconnected the USB cable, reconnect it to the rear of the printer.
• Try to print.

Also, try updating the printer firmware and check if it helps.

Link to update the printer firmware.(Instructions on how to upgrade firmware are listed in this link: Click here)

Hope this helps! Keep me posted for further assistance.
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