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Upgrading to Windows 7
XP to Win 7
If you’re upgrading from Windows XP, you’ll need to do a clean install of Windows 7. You’ll have to reinstall your programs. Your data will be wiped off the hard drive. So, back it up.
Vista to Win 7
If you have a Vista machine, you can do an in-place upgrade. You dont have to reinstall your programs, and your data shouldn’t be affected. However, there are some Consideration - First, if you switch from 32- to 64-bit or vice versa, a clean install is needed. Whether you need a clean install or not, play it safe. Back up your data before installing Windows 7.
It is always good idea to backup all your data and programs - be in safe side backup everything rather than to feel sorry later . |
Visit this for more info - http://www.microsoft.com/windows/windows-7/get/upgrade-considerations.aspx