I guess i have a few obvious questions: what are you using? a laptop or a pc? why don't you have any backup or restore disk? answer this and would be easier to help you
Come on guys, isn't impossible to have a pc or laptop with vista, xp or any other os without have a disk, if you go and buy a pavilion it comes with 2 partitions one called C and another called D or anything like that with the information that you need to create the "rescue" disks or "restore" disks... so, he may be on this situation, and is not the first one in this world who doesn't have the disks
Now concentrate in the situation, if your laptop or pc have anywere in the hd the backup, you can change the botting settings from the bios and then start the pc from the second partition and try to format or fix the problem, but i'm not sure if i explain my self as well, anyway you have an option there that you should look for
Wish you luck solving your problem
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