Internet Explorer 6 biggest block to Windows 7

Don't over-test, Microsoft urges.

Microsoft's ongoing battle to rid the world of its much-maligned Internet Explorer 6 browser has had lasting effects on upgrade paths, according to the company's principal compatibility lead.

The browser, hated by web developers and users alike since its launch ten years ago, continues to maintain a footing in many countries.

China has the largest user base with 30.5 percent of all web activity through IE6, according to Microsoft's countdown website.

The browser had even become the subject of a falsified survey that claimed its users were "dummies".

Though Australia maintains the second lowest rate of IE6 use globally, at two percent of traffic, Microsoft principal compatibility lead Chris Jackson said the corporate world remained a hold-out.

Major enterprises were known to maintain high deployments of Internet Explorer 6, along with ageing installations of Windows XP.

The ten-year-old browser, Jackson said, had become the "number one blocker of Windows 7 deployments that we have right now".

Microsoft has continued to push for upgrades of its browsers, operating systems and productivity suites across the board in order, it said, to maintain business agility and data security.

But the company's reticence around the issue in past years had failed its more recent, concerted effort.

"To be honest, we weren't really looking that much at [Internet Explorer]," Jackson said.

"When we were looking at Vista [and] then Windows 7, of course it becomes part of the strategy but from an engineering standpoint we never looked that hard at [IE6] because [IE] didn't seem like a hard engineering task."

Microsoft has since tried multiple tactics, including the countdown website and pulling corporate support for the product three years ago.

The software giant estimated that up to half of companies refusing to follow the upgrade path were unable due to a web app only being compatible with the aged browser.

Third parties had also begun to offer plugins for newer versions of the browser that allowed companies to run a virtualised instance of the older version.

"You can't simultaneously say, 'We need support therefore I can't go IE 8' while running an unsupported [browser] version," Jackson said. "It's logically inconsistent.

"I think the big thing right now is let's start to establish momentum."

Don't over-test

Jackson said Australian businesses had largely led the way in rationalising critical applications and only testing those deemed critical should they fail during an upgrade..

"The formula I put out there is, if the cost of testing is less than the cost of failure multiplied by the probability of failure, you should test," he said. "Otherwise, you shouldn't.

"You don't have to test anything, really. The reason you test is not to fill a check box, you're just trying to manage your risk and cost.

"You don't want to be the guy who put you out of business and at the same time you don't want to be the guy who made the migration project cost you $50 million just because you were being overly cautious."

However, Jackson said the test phase was about risk management rather than succumbing to the fear of potential issues.

"We don't have to wait until we've handled absolutely everything before we get the new browser. Now we can go much sooner, we only test the ones that actually fail in real business scenarios."

James Hutchinson travelled to TechEd 2011 on the Gold Coast as a guest of Microsoft.