After the "March 12, 2019—KB4489899 (OS Build 17763.379)" update on my one year old 15 inch Surface Book 2 the touch screen no longer works and the laptop will not completely power off. I worked thru removing the touch screen driver and letting Windows reinstall it but no joy. The touch screen also is not responsive in the UEFI interface which according to the troubleshooter at "https://support.microsoft.com/en-us/help/4023476/surface-touchscreen-problems-with-touch" means there is a hardware failure. However, I find this conclusion suspicious since the touchscreen failure and the power issue described below occurred after the update. When I shutdown via either the button or Start/Power/Shutdown the machine does not completely power off. The keyboard backlight and "Fn" key light remain illuminated. I have to press and hold the power switch for nearly 30 seconds to completely power off. I found in "Control Panel/Power/Power Buttons" that the "Fast Startup" was disabled so I enabled that and now the laptop almost immediately powers completely down but to start the laptop I now have to press and hold the power button for nearly 30 seconds. So after the update "Fast Start" really means fast and complete shutdown but very slow start up. I didn't have this behavior before the update. Anyhow, just curious if anyone else has encountered this and welcome suggestions/solutions. Thanks in advance.