What do you mean "after sanitized"? Was the drive wiped? That message you are getting is normal then, it's trying to find a way to boot, and is looking for a network boot device, can't find it.
You need to boot to an operating system disk and re-install the OS on the drive that was wiped.
As an FYI, that is not an issue with the laptop not turning on, but a boot issue. Not turning on would be you hit the power button and nothing happens.