Hi I have the same issue, intermittent dead spot top left of the screen, always fixed by a reboot. Theory: somehow related to the type cover, when closed the dead spot is exactly aligned to a rectangular patch to the left of the trackpad and below the keyboard where it touches the screen? Also I only ever see it after charging overnight with the type cover on and closed. Could be wrong, I'm going to test these theories.
Yes, this! (although I think you meant calibration, CT...) I posted this fix a while back on this forum in another thread. Worked perfectly for me (SP3, i7, 250 GB, Win10) for this problem. Try it before returning, resetting, etc.People has reported that using this tool fixed their calculation issues
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