That's not f7 or f10, that's f8 (type repeatedly after the BIOS is ready with POST). However, it's not sure to help.
Why did you force shutdown?
Kees
So my hp 4540s laptop with win 8 won't get to desktop.
After i force shut downed it started flashing after the hp logo (turning from gray-blue to black) I tried pressing F7 and F10 while booting up to enter safe mode but with no success.
I would be glad if you could help me.

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