Microsoft will begin pushing Internet Explorer 8 (IE8) to enterprises next month, the company announced this week.

The decision to turn on IE8 updates will set businesses scrambling to either test the new browser or block the update, which replaces older editions such as IE6 and IE7 that many companies now require.

Microsoft will flip the switch for IE8 delivery via Windows Server Update Services (WSUS) on Aug. 25, said Eric Hebenstreit, a lead program manager on the IE team. WSUS is Microsoft's most popular tool for deploying patches within businesses.

The IE8 upgrade will be made available as an "Update rollup," said Hebenstreit in a post to the IE blog on Monday.

That means systems running Windows XP, Vista, Server 2003 or Server 2008 will automatically grab IE8, assuming the organization configured WSUS to auto-approve "Update rollup" packages.

Hebenstreit said that companies that don't want IE8 should turn off auto-approve for "Update rollup" packages in WSUS prior to Aug. 25, then on the next sync, decline the IE8 update. They can later re-enable auto-approve.

Earlier this year, Microsoft said that it would start serving IE8 to WSUS users in July; Hebenstreit did not give a reason for the month-long delay.

Microsoft released IE8 in March, but waited a month before pushing the new browser to end-users via Windows Update (WU), the primary update service for consumers and smaller businesses. Before that, it had released a toolkit to block the new browser from reaching machines through WU; the toolkit, however, does not block IE8 upgrades pushed by WSUS or Systems Management Server (SMS), another Microsoft patch manager.

The toolkit, which is still available from Microsoft, will stymie IE8 deployment indefinitely. According to Web metrics firm Net Applications, IE8 accounted for 7.6 per cent of all browsers used in May, the most recent month for which data is available. Although Net Applications typically issues new browser market share numbers the first of each month, it has delayed June's data pending a review for what it said was " significant variations in browser and operating system statistics."

In other upgrade news from Microsoft, the company said yesterday that it had released the remaining 31 language-specific versions of Windows Vista Service Pack 2 (SP2) to Windows Update.

Microsoft posted Vista SP2 for download in May, and after a delay, began pushing the English, French, German, Japanese and Spanish editions to users via Windows Update on May 26.