Read Grif's ideas at https://www.cnet.com/forums/discussions/white-box-flashes-on-screen-windows-10/
If you want to find all things that autorun, read up about AUTORUNS at:
https://docs.microsoft.com/en-us/sysinternals/downloads/autoruns
Had to return my Dell Inspiron laptop 15-5332 for repair, keyboard and touch pad was replaced. Now I'm seeing little white boxes appear in left corner on display start up. Looked in msconfig and cmd. I'm I looking in the wrong place? If so where should I look. http://i63.tinypic.com/2dakqr8.png

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