I have the same problem constantly reoccurring and usually try any combination of the following: 1. Press the area around the top right (if landscape, bottom right if portrait) corner of the screen until I see my touch being registered by the touchscreen. 2. Uninstall the I2C HID (marked with “!” inside a triangle) and then “scan for hardware changes” – however, this requires a mouse to be connected. 3. Repeat No. 2 above, until I no longer see the exclamation mark sign. 4. Restart the machine Most often, I use No. 2 then do No. 1 (in that sequence). Nowadays I carry a mouse with me all the time, since even midway through using the tablet the screen often freezes. Really, this often almost pushed me to the brink of selling this otherwise wonderful machine.