Microsoft Windows 8 upgrades

Microsoft has sold a total of 4 million upgrades to Windows 8 over the first few days.

Since its launch on 26 October, Microsoft sold 4 million upgrades to its latest operating system over its first weekend on sale, according to The Verge. Microsoft said this was a 'spectacular start' to the Windows 8 launch. Read our: Microsoft Windows 8 review.

Microsoft CEO, Steve Ballmer, gave the statistic at a keynote address yesterday. He mentioned the firm's Surface tablet which has gone on sale in its Windows RT form but gave no figures on units sold so far. How to upgrade to Windows 8.

The 4 million figure may sound a lot but Microsoft has over 1 billion existing Windows users worldwide to there's some way to go yet. Users can upgrade for as little as £14 in the UK. See also: Windows 8 price in UK.

It's been a big month for Microsoft as it has launched not only Windows 8 and its Surface tablet, but also Windows Phone 8.

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