Before buying the upgrade, check to make sure your machine is strong enough to run Windows 8. Microsoft lists the system requirements here: http://windowsupgradeoffer.com/en-US/Home/ProgramInfo .
Not sure if you have what it takes? Microsoft has an upgrade tool that will stop you if you try to buy Windows 8 without the requirements. The tool will also warn you of software that might need updates to work on Windows 8. Go to http://Windows.com to get started.
If you're upgrading from Windows 7, the tool will let you keep settings, personal files and applications. You can migrate settings and files from Vista and files only from XP. You'll also have the option to start fresh and bring nothing to Windows 8.
— Keep older versions of Windows:
Do nothing if you do not wish to upgrade to Windows 8.
Most machines now on sale will have the new version of Windows, though it's still possible to buy Windows 7 machines or upgrade to Windows 7. You may have to order online, and your choices may be restricted to gaming or business-oriented machines.
Microsoft hasn't said what the cutoff date for Windows 7 will be, but expect to be able to buy Windows 7 as an upgrade for another year or preinstalled on a new machine for two more years.
After Windows 7 came out in October 2009, for instance, retailers were still allowed to sell boxed versions of the predecessor, Vista, until October 2010. PC makers were able to sell Vista machines until October 2011.
Microsoft plans to continue providing technical support for Windows 7 until Jan. 14, 2020.
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