Error notebook samsung np300e4c Boot menu is empty
I was searching months for a decent solution for this problem with same NP Samsung model. There are an incredible key-combination to boot from DVD-ROM and finally to get access.
First thing is to reset bios configuration with RTC BIOS pins, located besides RAM slots (alternatively, you can remove the CMOS battery for a moment). Then, insert a bootable USB drive or DVD-ROM and automatically press Fn+F3 (for DVD boot) or Fn+F5 (for USB boot).
If that doesn't work, try with Ctrl+F keys. If you have any OS installed on your HDD this will make it start.
I know, is not the solution for this problem, but an alternative to "jump it". Hope it works for you!