How to format my dual boot HDD with windows and ubuntu?

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http://askubuntu.com – I started installing Ubuntu 12.10 on my windows 7 (64bit), but then I installed a new windows and therefore deleted the old windows. I now want to uninstall Ubuntu and GRUB, but my WUBI-uninstaller.exe is not working, and I can't seem to find the Linux partition on my hard drive. I just want to do a complete format of my HDD without rendering it useless... (HowTos)