But, what version? We need to be exact here.
What do you mean when you say the PC will not start up? Will it go to the bios? Will it start to boot, then hang? Are there any error messages? Have you created a repair disk/stick?
Be very specific about what happens when you try to boot.
It ran an updatea few days ago, but I can't even get to my bios screen. thats what it mean going black. the version is 1903 and nothing happens with my pc when I turn on the power.