Microsoft's Internet Explorer 10 (IE10) doubled its usage share last month, and now accounts for nearly 11% of all copies of IE in use, a Web measurement company said today.

IE10, which Microsoft launched last October for Windows 8 and in February for the far-more-popular Windows 7, doubled its usage share within IE from 5.3% to a month-ending 10.8%, data published by Net Applications showed.

The browser's quick rise -- as recently as January, it accounted for only 2.3% of all copies of Internet Explorer -- was triggered by the start of an automatic update from 2011's IE9 to this year's IE10 on Windows 7 PCs.

IE10 was the first browser released by Microsoft since it changed its upgrade policy in late 2011. Rather than seek user approval before upgrading IE -- the previous practice -- Microsoft adopted a Google Chrome-like "silent" scheme that automatically installs the newest browser suitable for that version of Windows.

IE10 supports only Windows 8 and Windows 7, leaving Windows Vista stuck with IE9, just as Windows XP has been frozen at IE8.

Virtually all of IE10 gains were apparently through the upgrade process -- rather than in persuading users of rivals' browsers to switch -- as IE9, the previous standard on Windows 7, dropped to 32.6% of all copies of Internet Explorer from 37% the month before.

IE9 peaked in February with a 38.8% share of all copies of Internet Explorer.

Businesses can block IE10 from being automatically installed on their machines by deploying a toolkit Microsoft issued two months ago, or by using the standard update management tools, Windows Server Update Services (WSUS) or Systems Management Server (SMS).

IE8 remained flat at 41.4% of all copies of Internet Explorer, and if analysts are correct, will remain the most popular version of Microsoft's browser (free registration required) because not only is it the most modern available for the stubborn Windows XP, but it has also been adopted as the standard by many enterprises.

Nor did Microsoft make any progress last month in killing off IE6, the 2001 browser it's been trying to eradicate for years. IE6 was used by 11.1% of all those running Internet Explorer, a higher percentage than IE10.

Other browsers, including Mozilla's Firefox and Google's Chrome, remained flat in Net Applications' measurements as well, with Firefox ending April with a 20.3% usage share and with Chrome accounting for 16.4%.

IE's overall share also didn't change in April: Microsoft's various browsers garnered a usage share of 55.8%, steady for the first time since September.

Net Applications measures browser usage by tracking unique visitors to some 40,000 websites operated by its customers. More information on the company's metrics can be found on its website.

IE8 had the largest share of Internet Explorer usage in April. (Data: Net Applications)

This article, Microsoft's browser auto-update pays off as IE10 share doubles, was originally published at Computerworld.com.

Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, on Google+ or subscribe to Gregg's RSS feed . His email address is gkeizer@computerworld.com.

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