Fix a Touchscreen That Does Not Line Up with Your Finger

**Get-PnpDevice** lists the digitizer separately from the display. A missing HID touch device explains a screen that does not register taps at all.

Get-PnpDevice -Class HIDClass | Where-Object FriendlyName -match 'Touch|Digitizer|Pen' | Select-Object FriendlyName,Status,InstanceId
Get-CimInstance Win32_PnPEntity | Where-Object { $_.Name -match 'Touch Screen|Digitizer' } | Select-Object Name,Status,ConfigManagerErrorCode
Get-CimInstance Win32_DesktopMonitor | Select-Object Name,ScreenWidth,ScreenHeight

A stored calibration from a different resolution or orientation offsets every tap. Resetting before calibrating again avoids building on the wrong data.

control /name Microsoft.TabletPCSettings
# Display tab > Reset > OK
Get-ChildItem 'HKLM:\SYSTEM\CurrentControlSet\Control\TabletPC' -Recurse -ErrorAction SilentlyContinue | Select-Object -First 10 Name

The calibration matches the digitizer grid to the panel. Using the same input you will use daily gives the better result, and the crosshairs must be hit exactly in the centre.

control /name Microsoft.TabletPCSettings
# Display tab > Calibrate > tap each crosshair in the centre
# do not use a pen if you will tap with a finger
Get-ItemProperty 'HKLM:\SYSTEM\CurrentControlSet\Control\TabletPC' -ErrorAction SilentlyContinue | Select-Object * -ExcludeProperty PS*

A calibration is per orientation. A tablet used in portrait and landscape needs both, and a scaling change of the desktop invalidates it.

Get-DisplayResolution 2>$null
Get-ItemProperty 'HKCU:\Control Panel\Desktop' | Select-Object LogPixels
Get-CimInstance -Namespace root\wmi -ClassName WmiMonitorBasicDisplayParams | Select-Object InstanceName,MaxHorizontalImageSize,MaxVerticalImageSize

Edge dead zones and jitter after a firmware update are driver problems. The vendor's HID driver usually fixes what calibration cannot.

Get-PnpDevice -Class HIDClass | Where-Object FriendlyName -match 'Touch|Digitizer' | Select-Object FriendlyName,InstanceId
Get-CimInstance Win32_PnPSignedDriver | Where-Object DeviceName -match 'Touch|Digitizer' | Select-Object DeviceName,DriverVersion,DriverDate
Get-CimInstance Win32_BIOS | Select-Object SMBIOSBIOSVersion,ReleaseDate

A grid drawn to the screen edges shows the remaining error. Tapping each corner and each edge centre is the practical test.

Add-Type -AssemblyName System.Windows.Forms
$b = [System.Windows.Forms.Screen]::PrimaryScreen.Bounds
"screen: $($b.Width)x$($b.Height)"
Start-Process ms-settings:display
Get-PnpDevice -Class HIDClass | Where-Object FriendlyName -match 'Touch' | Select-Object Status