Dell Venue 8 Pro 5855 Touchscreen inverted on Y Axis

  This seems to be a common issue as I am having the same issue with my venue 8 pro 5830. I installed a new screen and when try to move the mouse it goes in opposite direction and same on the OSK if I tap 1 the back space button lights up, but I have put an external key board and mouse which works fine. Mine also came up with the issue of Bit Defender on boot aND I have the code but it won't take it so I'm locked out. One more thing when I got my tablet it was having the issue you have and I found a post somewhere that said to change something in BIOS and that fixed it, but I don't remember exactly what I changed and I would try but mine won't let me get there because of Bit Defender, so someone else on win 10 forum said to D/L win 10 on flash and reinstall again and that should fix it , but you might want to use external key board and mouse boot to bios and look at items in the video or screen then hardware see if the default value has changed, Sorry I'm not more help but I know I've fix min before with this problem but if you do find how to fix it please post it .