Microsoft has warned businesses to begin Windows 7 deployments as support for Windows XP will end in less than 1,000 days.
The software giant will offer support for the 10-year-old XP operating system (OS) until 8 April 2014 before discontinuing automatic fixes, updates and online technical assistance.
Stephen Rose, Microsoft senior community manager, said in a blog post, "it's time to move from good enough" to upgrade to Windows 7.
"On 8 April 2014, security patches and hot fixes for all versions of Windows XP will no longer be available. So PCs running Windows XP will be vulnerable to security threats," said Rose.
"Furthermore, many third-party software providers are not planning to extend support for their applications running on Windows XP, which translates to even more complexity, security risks and, ultimately, added management costs for your IT department if you are still managing Windows XP environments," he said.
Rose cited Gartner research showing over 50% of companies will experience increased support costs by failing to deploy Windows 7 before the end of support for Windows XP.
Ovum principal analyst Richard Edwards believes Windows XP will be the last major corporate version of Microsoft's Windows OS as businesses deploy alternative desktop computing models over the next three years.
"Most businesses and institutions gave Windows Vista a wide berth because of technical and compatibility issues, so Windows 7 has quickly become the operating system of choice for new PC deployments," he said.
"But, with sales of tablet and thin-client computing devices growing rapidly, and alternative application delivery architectures starting to take hold, we believe that by 2014 many organisations will have decided to adopt alternative end-user computing models, thus making Windows XP the last major corporate version of the Windows desktop operating system," Edwards said.
Brandon LeBlanc, Microsoft Windows communications manager, also confirmed on a Microsoft blog that Windows Vista SP1 will no longer be supported. Extended support for Microsoft Office XP has also now ended.
Microsoft is offering a 90-day free trial of Windows 7 Enterprise.