September 29th, 2017, 12:53 PM
Have you run a scan with Malwarebytes?
September 28th, 2017, 11:13 AM
Do you have AVG installed? If yes, possibly useful link:
https://www.bleepingcomputer.com/forums/t/581007/white-box-appeared-on-desktop-fix-common-computer-problems/
September 28th, 2017, 12:08 AM
Can you see your desktop icons?