I had two partitions on my hard drive labeled as unknown in gParted that showed up out of nowhere. I use 3 OS's on my computer, Windows which I just recently deleted, Backtrack5, and Ubuntu 12.04 which I am running gParted on. I tried to delete both of the suspicious partitions assuming it was a rootkit or something similar I got from Windows but was only able to format one; the other refused both deletion and formatting. Can someone help me remove these partitions? Look at the partitions labeled "Unallocated" and "/dev/sda6".