Cause:
PS2 Mouse Driver – Booting a machine without a keyboard, or with a USB keyboard can cause this problem

Fix:
Stop this Service from starting – Note this SHOULDN’T affect your keyboard but if it does have a USB keyboard handy and DON’T disable the PS2 Ports in the machines BIOS

Start > Run > Regedit {enter}
Navigate to, HKEY LOCAL MACHINE\SYSTEM\CURRENTCONTROLSET\SERVICES\i8042prt
On the right hand pane change Start from 1 to 4 (disabled)

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