Windows XP support, but time may have already run out for some companies still hoping to carry out a conventional migration.
Studies suggest XP still accounts for about 40 percent of installed desktops in the UK, even though Microsoft has designated 8 April 2014 as the day support ends for the venerable operating system, first released to manufacturers in August 2001.
That one-year window before Windows XP's end of life is not enough time for organisations planning to make the move using traditional methods, according to Ovum principal analyst Roy Illsley.
"If they were doing the traditional migration — which people have done to get to XP from Windows 95, for example — then on our analysis if there have anything more than a couple of hundred PCs, they really haven't got time to do that. Not unless they throw an absolute mammoth amount of manpower at it," Illsley said.
"Generally, for an upgrade you're looking at — depending on size — anything from two to three years from start to finish to do it properly. But that's doing it the traditional way."
In 2010of 9,000 staff using 2,500 desktops and laptops from XP to Windows 7 and had completed the task by late 2012.
Illsley thought many of those organisations that have still to make the move from XP would look to desktop virtualisation for a solution.
"If they do a desktop virtualisation-type approach, whether they go fully desktop-virtualised or whatever, they can still get some useful tools to help get over 80 to 90 percent of the problem and they've still got time to do that," he said.
Unsupported XP applications
Research from Accenture-and-Microsoft-owned software consultancy Avanade suggested that 52 per cent of UK IT departments have yet to put in place a strategy for dealing with applications that currently run under XP, which continues to account for 43 percent of enterprise desktop infrastructures.
"The issue is really those 10 percent of applications that won't or can't migrate and those are the ones where now people have got to start really thinking, 'What's my contingency for that'," Illsley said.
"Because if there is an app that they can't do without, they are going to have to run that machine running the app in XP or try and find some way of running that in compatibility mode — if it will work until they can get off it," he said.
"That's the real cruncher. If they bite the bullet and say, 'Right, that app — we're just going to wind it down and replace with it with this one', then they'll be OK.
"It is pretty much the crossroads. Now is the time that if they haven't started thinking about doing it, then they have really have to — and not in the traditional way but in a radically different way," he told ZDNet.
New figures from software consultancy Camwood suggest one in five companies still using XP plan to continue using it after Microsoft support ends.
Illsley said pursuing that approach would render an organisation vulnerable to security breaches.
"When no more updates are coming through for XP, it's a security risk. If somebody finds a weakness with it, Microsoft aren't going to be releasing patch updates to fix problems," Illsley said.
"If your business hasn't got anything sensitive on there and it's just a standalone PC, you could argue that the effect is actually minimal. But if it's a PC accessing a corporate network doing important stuff, they've got to upgrade because they would be at severe risk," he said.
Illsley added that he expects most organisations to move to Windows 7 rather than Windows 8 and probably swap existing apps for SaaS alternatives. He also thinks some companies may go for open-source desktops.
"Over the past couple of years I've noticed a definite change in perception about open source. It's not beyond the realms of possibility that a number of people will go for Linux on the desktop."
He added that some smaller organisations in certain specialised sectors might use a combination of Apple Macs and virtualisation technologies.
"But that will be quite a small number. We are expecting the majority of that 40-odd percent to move off XP and onto Windows 7," he said.