The move from XP to Vista entailed serious hardware upgrade costs, not to mention the soft costs of installation, training and support . If Vista offered security enhancements over XP, the benefits were more than overwhelmed by user dissatisfaction, upgrade headaches, and the cost.

With Windows 7, will enterprises continue to hold on to XP? It's unlikely, since Microsoft has announced an end-of-life deadline for XP in 2014, but the reality is that XP will be fully phased out long before then.

That's because hardware manufacturers are unlikely to offer XP on new machines much longer. As PCs are upgraded, Windows 7 will rapidly enter the enterprise , regardless of any resistance to operating-system upgrades.

Enterprises Advised To Upgrade

While the move to Windows 7 may be inevitable, IT shops won't resist to the very end of XP's life. Technology consulting firm Gartner Group issued a research note this week advising companies to switch over by 2012.

"Microsoft will support Windows XP until April 2014, [but users should] plan to be off Windows XP by the end of 2012 to ensure ongoing support by independent software vendors for new applications," Gartner analyst Stephen Kleynhaus wrote.

Software vendors and integrators will stop supporting XP "beginning in late 2011 and accelerating through 2012," Kleynhaus wrote. With migration likely to run 12 to 18 months, "organizations should therefore begin migration planning immediately to maximize their options and enable a controlled and cost-effective migration to Windows 7," the analyst said.

Vista Memories Create Reticence

A recent survey of enterprise IT shops by Information Technology Intelligence Corp. (ITIC) and Sunbelt Software -- shows some pent-up demand for the new OS. According to the survey, 60 percent of companies plan to upgrade to Windows 7 in relatively quick order. Forty-nine percent said they would upgrade in the next 12 months, and 30 percent said they would get it done in just six months.

On the other hand, a large percentage of enterprises are maintaining a wait-and-see attitude, driven in part by memories of bad experiences with Vista. "There's a certain reticence based on the prior experience," Charles King, principal analyst with Pund-IT, said in a telephone interview. "But from talking to people who have tested Windows 7 thoroughly, I think Microsoft has a winner this time around. Windows 7 is delivering as big a step forward as XP did back in 2001."

Once companies start doing serious evaluations of Windows 7, it's likely that many concerns will be allayed, King added. "A larger number of companies are going to move ahead in advance of the service pack. If companies see the security enhancements that they're looking for, adoption may well speed up."