The easy upgrades to Windows XP have already been done, migration experts said, predicting that a large number of enterprises will still be running the aged OS a year from now.
Microsoft plans to retire Windows XP from all support, including security patches for the public, in 52 weeks, on April 8, 2014.
But the experts said that while many customers have left XP in their rearview mirrors, those who haven't are among the world's biggest corporations and organizations, which in some cases have tens of thousands of XP PCs.
"Our studies have shown that large enterprises have made the least progress in migrating from Windows XP to Windows 7, with 64% yet to complete their migration," said Betty Junod, the director of desktop product marketing at VMware, the U.S. company known for its virtualization software. Mid-sized companies have made better progress, said Junod in an email: Slightly more than half -- 52% -- of those firms have not wrapped it up.
Browsium, a Washington state-based company whose Ion lets customers run older versions of Internet Explorer inside newer editions, agreed. "[The] easy Windows 7 migrations [have] already [been] done. What's left are the difficult and expensive migrations facing the largest of enterprises," the company's president and COO, Gary Schare, wrote in a blog post last week.
Schare elaborated in an interview Monday. "Our typical customer is a big, old organization, banks, health care, government," Schare said. "And every single one of them is stuck on its migration [from XP to Windows 7]."
Browsium's customers use Ion as a migration aid, because it lets them run legacy in-house Web apps, often designed for IE6, the browser that shipped with XP in 2001, in newer versions, such as IE8, that Windows 7 supports.
It's not that enterprises don't know about the impending retirement, or have ignored the deadline, said Schare. But circumstances, ranging from tight budgets to XP's by-now-solid reputation, have interfered.
He also wondered whether some organizations have simply balked because they had had no experience in migrating thousands of desktops to a new OS. "The move from Windows NT or Windows 2000 to Windows XP was the last time organizations really migrated," Schare wrote on Browsium's blog, noting that virtually every enterprise skipped 2007's Windows Vista. "Who remembers how to migrate desktops anymore?"
In some places, the situation is even more dire. On Monday, U.K. migration firm Camwood cited a survey of 250 IT decision makers from companies with 2,000 or more employees. According to that poll, just 42% of the represented enterprises have started their shift from XP.
"In these tough economic times, it is not surprising that business leaders do not want to invest a substantial amount of money in something that essentially isn't broken, as is the case with Windows XP today," said Adrian Foxall, Camwood's CEO, in an email.
Of the roughly four-in-ten companies that had begun migrations, a third were three-quarters of the way done, and half said they were about 50% through the move.
Those may make the deadline, but others will clearly not: Nearly 20% of the IT leaders surveyed who said their firms were currently running Windows XP acknowledged that they plan to continue using XP after Microsoft pulls support.
Schare from Browsium said he has heard the same from his customers. "Everyone knows about the deadline, they want to do [migrations], but many are telling us that they won't finish until late 2014, or even early 2015," Schare said.
The end of the low-hanging upgrade fruit may be one reason why Windows XP's decline has slowed. Data published by Web metrics vendor Net Applications, which tracks operating system usage, shows that the long slide of XP's usage share has stalled since the first of this year. The slowdown started earlier, however: In the last six months, XP's average monthly decline was less than half the average of the six months before that.
Net Applications' statistics can also be used to roughly plot XP's future usage share. If the average decline of the last 12 months holds, XP will still account for 33% of all PCs expected to be running Windows at the end of April 2014.
Which prompted Schare, as it has others, to wonder if Microsoft might, just might, recant and extend XP's support if millions of its customers were still running the old OS -- and vulnerable to newly-discovered exploits -- after the deadline.
"What's going to happen next April if a large section of Windows users are not patched?" Schare asked.
Microsoft did not reply to that question, or others, on Monday.
But the company has been beating the migration drum. As far back as June 2011, a Microsoft manager claimed it was "time to move on" from XP. And it's kept up that drumbeat, most recently on Monday when it highlighted its Go2Modern website and rolled out a discount on Windows 8 and Office 2013 to small- and mid-sized businesses running Windows XP Professional.
Even so, Microsoft has been mum on how many Windows XP PCs it believes are still in use, how many will still be running a year from now, and how it expects customers, enterprises in particular, to acquire huge numbers of new machines in just 12 months.
Most analysts believe it's impossible for a company to migrate to a new operating system from a standing start in under 12 months. Microsoft admitted as much Monday. "Based on historical customer deployment data, the average enterprise deployment can take 18 to 32 months from business case through full deployment," said Stephen Rose, a senior product manager in the Windows group, on a company blog.
Microsoft has not put a number to XP's current corporate share, but the Redmond, Wash., software developer knows it's large: In January, during the company's last quarterly earnings call, CFO Peter Klein said 60% of all enterprise PCs were running Windows 7. Since few businesses adopted Windows Vista and even fewer have yet to jump on Windows 8, the remaining 40% must, by default, almost all be running Windows XP.
Microsoft's given no hint it will extend the deadline, but instead has repeatedly said it will end support and stop security updates in less than a year. If that's the case, hundreds of millions of PCs -- by Computerworld's calculation using Net Applications' data, 450 million -- will be running without the safety net of Microsoft's patches.
Schare simply couldn't believe Microsoft would expose that many of its customers, and by extension, the entire Windows ecosystem, to potential security threats. "They have time to change their mind," he noted. "If, with just three months to go [to April 8, 2014], there's 25% or 30% still running XP, maybe they would."
Not likely, others have declared. "I think they have to draw a line in the sand," said John Pescatore, at the time an analyst with Gartner, in a Dec. 2012 interview. "They've supported XP longer than anything else."
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, or subscribe to Gregg's RSS feed . His e-mail address is email@example.com.
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