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i had installed Windows 7 in my laptop and tried to install ubuntu recently. This attempt damaged OS windows 7 and unable to boot up. I have tried to repair with Win7 DVD and failed. Again I have tried to install Windows 7 with DVD, found no separate partition (earlier there were 3 nos of partition) in hard disk. Expecting all data remains in HDD. I would like to install Win 7 without deleting existing data. Kindly help me to install OS without formatting / loosing the data.