Microsoft has confirmed that the official release date for the new Windows 7 operating system will be 22 October.

In an announcement on the company's Windows blog Brandon LeBlanc, Windows communications manager, said that the launch date was now set and the company would begin selling the new operating system earlier than the previously announced date of 2010.

Final code development will be finished this month, he said, and manufacturers will start getting the code next month, at which point Windows Server 2008 R2 should also be ready.

"Release to manufacturing [RTM] is an important milestone," wrote LeBlanc. " We anticipate making the RTM code for Windows 7 available to our partners sometime in the second half of July. We also expect to be able to make RTM code for Windows Server 2008 R2 available to our partners in this time frame as well. "

The release will mean that Windows 7 will be in place for the crucial Christmas shopping period, when hardware sales are strongest. Microsoft is also instituting a scheme to ensure that sales do not die off in the meantime called Windows 7 Upgrade Option Program.

Under the scheme, which is still being finalised, users who buy a computer with Windows Vista will get a free upgrade to Windows 7.

Microsoft should avoid the problems that the similar Vista Capable campaign caused because Windows 7 should not need a major hardware upgrade over existing systems.

Windows 7 was released as a beta in January and has had largely positive reviews. It has taken a little under three years to develop, in contrast to Vista which took five years and has been unpopular with buyers.