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I installed Ubuntu 12.04 on my laptop using the Windows Interface installer and it works just fine but now I want to get rid of Windows 7 permanently because it is simply a burden and uses up 50GB of disk space and is virtually usless to me now. Since this type of installation uses Windows as the "host" OS if there is any problem with windows in the future I'm afraid that may compromise the functioning of Ubuntu. Is it possible to do this while Ubuntu is still on my primary drive? I have all my data backed up on Drive D:\ So can I format only that part of C:\ that has Windows on it leaving Ubuntu intact or do I have to format the entire C:\ drive?