I have windows 10. A while back bubbles started to appear on screen when I turned the computer on. I had a problem typing in my password but managed to do so bit by bit. I then disabled touch screen and had no further problems until yesterday when an update to windows 10 was installed. Now I can’t even type in my password as the box flashes black and white, bubbles appear on screen and the cursor moves constantly. If I could log in I’m sure I can sort the problem as before but how can I enter the password. Any ideas?