1.Find your Windows 7 product key: Typically this 25-character alphanumeric string is printed on a sticker affixed to your PC or on documentation included with your PC. Alternatively, you can use a keyfinder program such asMagical Jelly Bean Keyfinderto pull your product key from the Registry. You need your product key to reinstall Windows.
Magical Jelly Bean Keyfinder helps you round up your serial numbers.
2.Download the ISO file for the version of Windows 7 you own:
The above links point to Digital River, a licensed distributor ofMicrosoftsoftware. These downloads are each over 3GB, and your product key will work only with your edition of Windows, so make sure to select the right one.
3.Download theWindows 7 USB/DVD download tool. This utility lets you copy your Windows 7 ISO file to a DVD or USB flash drive. Whether you choose DVD or USB makes no difference; just confirm that your PC can boot to the media type you select.
4.Boot your computer using the Windows 7 DVD or USB flash drive. Follow the prompts to prepare the destination hard drive and install Windows.