Computer crashes when ethernet isn't plugged in

[BenjaminR]

So my friend has had this problem for ages. His computer will crash once every 3 days if the ethernet cable is plugged in. But if you unplug the ethernet cable it crashes every couple of mins. I have already tried removing the network adapter and he said it still crashes every 3 days ish.

So my question is. Is it the version of windows 10 he has? I originally installed a trial version on the computer but he has recently signed in with his windows account he used on his laptop and he has windows 10 home 64bit.
So why on earth does plugging in the ethernet fix the computer from hard locking?

 

[SkyNetRising]

I'd check the pc for infections.

 

[BenjaminR]

I'd check the pc for infections.

We already tried Malewarebytes