How to Change Your Windows 8 HP Laptop to Touch-Screen Modeby David Weedmark
By default, an HP laptop with a TouchSmart display should always be in touch-screen mode. This isn't an option you can turn on or off in Windows 8. If your screen has stopped responding to your touch, HP recommends shutting down the laptop and cleaning the screen. If the TouchSmart display still doesn't respond when you turn the laptop back on, reconfigure its settings. If this fails to work, you can try a system restore or a system recovery.
Fixing Touch-Screen Settings
To reconfigure the laptop's touch-screen settings, type "Tablet PC Settings" (without quotes here and in subsequent commands) in the Windows 8 Search charm and then click "Tablet PC Settings" in the search results. You can then click the "Setup" button and follow the on-screen instructions. When you're finished, the touch screen should be working properly again.
Using System Restore
Microsoft System Restore is turned on by default on HP laptops, so you can use this to restore the laptop to a point in time when the TouchSmart display was working correctly. To launch this utility, type "Restore" in the Search charm. Click "Create a Restore Point" and then click the "System Restore" button. The on-screen instructions will guide you through the rest of the process.
Using HP System Recovery
Resetting your laptop to its factory default settings should get the touch screen working again. To use this method, disconnect all peripherals from the laptop, restart it, and type "Recovery manager" in the Search charm. Select "HP Recovery Manager" and then select "Windows Recovery Environment." Follow the on-screen instructions through the rest of the process.