It sounds like your white spot is "...caused by "burn in" - the same thing being displayed in the same place continuously for a long time. "
Disable whatever icon was displayed there from being displayed if you can figure out how to do that,
or to minimize any further damage caused by that, or to lengthen the useful life of the backlight behind the LCD screen in any case, set your Power Options in Control Panel to turn off the monitor after xx minutes (of user inactivity) so that no video is produced in that circumstance.
Moving your mouse or pressing a key will restore the display in a very short time after that has been triggered and the display has gone black
(The liquid crystal pixel grid does not produce light - it colors or lets through or blocks white light coming from the backlight in behind the grid. If there is any video at all on the screen, the backlight is on behind the LC grid (screen). The backlight for a conventional LCD display is a CCFL - Cold Cathode Florescent Lamp - it burns out eventually just like any other florescent lamp. )