Windows XP: Why is the enterprise so reluctant to let it go?

Inside the enterprise: Old operating systems refuse to die. Instead, they fade away.

Or, in the case of some of Microsoft's platforms, they seem to be continuing into old age, in rude health.

According to a recent research study by Netmarketshare, half of all Windows users are still running Windows 7, even though new PCs now ship with Windows 8.1.

More surprising, perhaps, is that Windows XP still accounts for a quarter of online users. This is for an operating system that was released in August 2001, which is certainly the Cretaceous, if not the Jurassic, period in computing terms. Moreover, Microsoft ended support for Windows XP earlier this year, leaving users potentially vulnerable to security risks.

The longevity of these old operating systems is hard to explain. We can't all be waiting for the return of the Start menu (dropped in Windows 8, and now slated for next year, if the rumours are true).

Certainly, there are some applications that only run on older operating systems and especially, older browsers, such as IE6. But most businesses should, by now, be in a position to work round those incompatibilities.

"There is a certain percentage of users out there who are just not going to change, until they are forced to change," concedes TK Keanini, CTO at Lancope, an security and performance vendor.

"By forced, I mean the computer stops working, or applications become dysfunctional. Until then, they are just going to go on doing what they have always done." But as Keanini points out, there are some real risks around XP in particular.

Budgetary constraints, and general inertia, could be other reasons. Sometimes, the adage "if it ain't broke, don't fix it" makes a lot of sense in IT. That certainly applies to Windows 7 still a robust and capable OS for many tasks though perhaps not for the now unsupported XP.

Budgetary constraints, though, are perhaps more of a factor. But so, too, is the changing make up of many enterprises' PC estates, or more accurately, their personal device estate.

"We have actually seen quite a lot of migration, but it has been spread out over a prolonged period of time," says Simon Townsend, chief technologist for EMEA at Appsense, the virtualisation and application management vendor.

"Another reason we may not hear of migrations is because many form what be called 'transformation'; just because it is not a migration doesn't mean, for example, that they're not upgrading or moving to VDI [desktop virtualisation] for example."

Operating system upgrades often go hand in hand with hardware upgrades, especially for smaller businesses that might not want to roll out a new OS on older hardware. With the economic pressures of the last few years, quite a few companies will have skipped a generation of upgrades, leaving older systems to run on.

As important is a shift to different types of computing devices altogether. Older desktop PCs might be gathering dust, as employees move to shiny new tablets, smartphones or even Chromebooks. Looking at the PC market in percentage terms may not give the full picture, as employees hold on to older machines for one or two office-based tasks, but do more work on newer, more portable kit.

But, with the growing costs and security risks associated with running older systems, it is well to plan for their well-earned retirement now.

Stephen Pritchard is a contributing editor at IT Pro.