Microsoft has revealed that Windows 8 will be released on 26 October.

微软透露，Win8将于10月26日发布。

The declaration was made at the firm's annual sales meeting and was published on its blog shortly after.

The firm has described the update as the most important redesign of its interface in more than a decade.

The announcement was made a day before the firm releases its fourth quarter earnings report. Analysts say it may post its first ever loss after writing down the value of a troubled takeover.

The firm paid $6.3bn (£4bn) for the online advertising service Aquantive in 2007 but has said the service did not perform as expected. As a result its earnings will be offset by a $6.2bn charge.

Touchscreen controls

The company's future efforts are now focused on its upcoming system software release.

Windows 8 includes a touch-controlled interface dubbed Metro as well as a more traditional desktop. 

It will be released in a version that runs on ARM-based chips for the first time, as well as versions for x86-based ones designed by Intel and AMD.

Some consumers will have delayed buying new computers ahead of the release, depressing Microsoft's sales in the meantime. 

However, many companies have continued with their roll-out of Windows 7 as it typically takes big firms' IT departments months or years after a major system update to approve its installation on workers' computers.