I remember struggling with one compound for half a day, I barely got mad.
Some small squares on the entire monitor.
I thought if the virus was completely new, or if the video card was gluing, in the end, I wanted to give up.
and what?
It turned out that the secretary, a good soul, behind some shit glued straight to her screen a transparent film with printOm, and this film was exactly the size of the frame of the monitor.
Most importantly, I asked her many times - "How long have you had these squares"?
It is "long ago", and what they are on the film - no googling.
He barely killed.