hi i got problem on boot loader. i just deleted a bactrack on windows 8 partition manager and everthing was fine the problem is when i reboot the laptop and error appear.. error: unknown filesystem
grub rescue>

i encounter same error like this on windows 7 and i search on google how to fix this issue but now i cannot enter on windows 7/8 installation i have change the 1st boot to my dvd but when i reboot. grub error is appearing.

i know there's a thread like this but i follow the step and still don't fix my problem... my laptop is samsung
Processor AMD e-350 processor
memory 2gb ram
amd radeon hd 6310

please help me thanks a lot