When I go to reformat my computer, I'm new to this. I inserted the windows xp professional disc and then went to install windows and it did stuff and when it said to reboot my computer it got to where it says delete the c drive and to like redo it all and wipe my computer i get an error. It says that I have necissary files on my c drive and that it needs to use to complete setup and i didnt delete it and now its taking all my computer space and I think that something is wrong here. How can i make it delete c drive when im formating and make a new one?