, a major release of the Microsoft Windows operating system, was available in six different editions: Starter, Home Basic, Home Premium, Professional, Enterprise and Ultimate. Only Home Premium, Professional, and Ultimate were widely available at retailers. The other editions focus on other markets, such as the software development world or enterprise use. All editions support 32-bit IA-32 CPUs and all editions except Starter support 64-bit x64 CPUs. 64-bit installation media are not included in Home-Basic edition packages, but can be obtained separately from Microsoft. According to Microsoft, the features for all editions of Windows 7 are stored on the machine, regardless of which edition is in use. Users who wish to upgrade to an edition of Windows 7 with more features could use until 2015 Windows Anytime Upgrade to purchase the upgrade and to unlock the features of those editions. Microsoft announced Windows 7 pricing information for some editions on June 25, 2009, and Windows Anytime Upgrade and Family Pack pricing on July 31, 2009.
Main editions
Mainstream support for all Windows 7 editions ended on January 13, 2015, and extended support ended on January 14, 2020. Since October 31, 2013, Windows 7 is no longer available in retail, except for remaining stocks of the preinstalled Professional edition, which was officially discontinued on October 31, 2016. ; ; ; ; ; ;
Special-purpose editions
The main editions also can take the form of one of the following special editions: ; ;
Upgrade editions
In-place upgrade from Windows Vista with Service Pack 1 to Windows 7 is supported if the processor architecture and the language are the same and their editions match. In-place upgrade is not supported for earlier versions of Windows; moving to Windows 7 on these machines requires a clean installation, i.e. removal of the old operating system, installing Windows 7 and reinstalling all previously installed programs. Windows Easy Transfer can assist in this process. Microsoft made upgrade SKUs of Windows 7 for selected editions of Windows XP and Windows Vista. The difference between these SKUs and full SKUs of Windows 7 is their lower price and proof of license ownership of a qualifying previous version of Windows. Same restrictions on in-place upgrading applies to these SKUs as well. In addition, Windows 7 is available as a Family Pack upgrade edition in certain markets, to upgrade to Windows 7 Home Premium only. It gives licenses to upgrade three machines from Vista or Windows XP to the Windows 7 Home Premium edition. These are not full versions, so each machine to be upgraded must have one of these qualifying previous versions of Windows for them to work. In the United States, this offer expired in early December 2009. In October 2010, to commemorate the anniversary of Windows 7, Microsoft once again made Windows 7 Home Premium Family Pack available for a limited time, while supplies lasted.
Upgrade compatibility
There are two possible ways to upgrade to Windows 7 from an earlier version of Windows:
An in-place install, where settings and programs are preserved from an older version of Windows. This option is only sometimes available, depending on the editions of Windows being used, and is not available at all unless upgrading from Windows Vista.
A clean install, where all settings including but not limited to user accounts, applications, user settings, music, photos, and programs are erased entirely and the current operating system is erased and replaced with Windows 7. This option is always available and is required for all versions of Windows XP.
The table below lists which upgrade paths allow for an in-place install. Note that in-place upgrades can only be performed when the previous version of Windows is of the same architecture. If upgrading from a 32-bit installation to a 64-bit installation or downgrading from 64-bit installation to 32-bit installation, a clean install is mandatory regardless of the editions being used.
Anytime Upgrade editions
Until the year 2015, Microsoft also supported in-place upgrades from a lower edition of Windows 7 to a higher one, using the Windows Anytime Upgrade tool. There are currently three retail options available. There are no family pack versions of the Anytime Upgrade editions. It was possible to use the Product Key from a Standard upgrade edition to accomplish an in-place upgrade.
