I have a dual boot system on dell xps 9000 with windows 7 and ubuntu. But after I performed system backup on it as requested by windows 7 I am no longer able to boot into the computer, instead at the beginning after bios I get the following message: Grub loading. The symbol ' ' not found. Aborted. Press any key... I tried to change bios booting config to starting with harddrive and it still returned the same message. Using windows boot disk only asks me to do another system backup or threatens to delete my harddrive completely. The only solution I have so far is to reinstall ubuntu, but that leaves 2 additional copies of ubuntu on my computer. Is there a simpler way to fix the situation so I can actually boot into windows? Thanks so much.