When that suddenly goes away, it can feel like you’re locked out of your machine.
These troubleshooting steps apply to any touch screen rig running Windows, iOS, or Android.
You should try them in this order, but some may not apply to your gear.

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Clean the touch screen and screen protector.
Dry off your smartphone.
Touch screens can also stop working, become unresponsive, or work erratically if it gets wet.
In that case, drying the phone out thoroughly sometimes fixes the problem.
There are several steps todrying out an Androidoran iPhone/iPod.
Gently tap each corner of the phone.
Gently tapping on each corner of the phone may cause it to reconnect.
If that doesnt work, fixing the digitizer requires taking the phone apart.
Remove the SIM card, memory cards, and peripherals.
Be sure to power down fully and unplug your machine first.
Turn on Safe Mode for AndroidorWindows Safe Mode.
Start with recently downloaded apps and go from there, deleting each one until the touch screen works again.
Adjust iPhone 3D Touch sensitivity.
Assuming the touch screen works at all, youll need to adjust that setting.
Go toSettings>Accessibility>Touch>3D & Haptic Touch.
Adjust the slider between light and firm.
Try turning off 3D Touch if the screen is still inaccurate or unresponsive.
Calibrate your Windows touch screen.
There’s a tool available that helps to reset the center of each touch you make on your unit.
If your touches seem slightly off, this might help restore everything.
Update touch screen drivers.
The latest drivers can often fix issues like this one.
Roll back the touch screen driverif a recent update caused it to break.
Disable and re-fire up the Windows touch screen.
If those don’t work, it’s time toget a new phone.
Newer devices don’t offer the option to reset or calibrate the touch screen since it’s rarely necessary.
Android stopped offering that option in version 4 of its OS, and Microsoft stopped after Windows 10.
This issue is typically resulting from a hardware problem but can often be resolved with some troubleshooting.