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I had Ubuntu 12.04 + Windows 7 installed, I didn't like Ubuntu hence I deleted the partition. But I forgot to fix the MBR. Also I cannot access the mutiboot option using F12 at startup. So when I start, I get the Lenovo screen with F2, F12 options but none work, and then the screen shows:
unknown filesystem grub rescue-
with commands ls I get:
(hd0) (hd0,gpt6) (hd0,gpt5) (hd0,gpt4) (hd0,gpt3) (hd0,gpt2) (hd0,gpt1) (cd 0)
and with set I get:
may be because I had installed my Ubuntu in gpt3 partition
can anybody fix this problem?