Redmond announces that computers based on the latest processors from Intel, AMD and Qualcomm will need Windows 10 to ensure they get updates.
Microsoft is phasing out support for Windows 7 and 8 on new PC hardware.
On Friday, Microsoft announced that computers based on newer chips from AMD, Intel and Qualcomm will need to be running Windows 10 to be guaranteed continued updates.
Machines that require Windows 10 to ensure continued support will be those running on processors based on Intel's Skylake design, released late last year, Intel's Kabylake family, due before 2017, AMD's Bristol Ridge, due this year, and Qualcomm's 8996/Snapdragon 820 architecture.
The move is likely to hit businesses the hardest. Firms are often slower than consumers to move to new operating systems, due to the complexity of managing upgrades at scale and ensuring compatibility with legacy software. For that reason they rely more heavily on the 10 years of support that Microsoft had, until now, provided for each Windows release - regardless of the hardware.
Even with that long-running period of guaranteed updates, when Microsoft dropped support for XP in April 2014, more than three-quarters of businesses in the UK were still running the venerable OS somewhere within their IT estate, according to one survey.
Microsoft's new timetable for support
To offset the effect of these latest changes on businesses, Terry Myerson, VP of Microsoft's Windows and Devices Group, said that it would continue to support Windows 7 and 8 on a selection of Skylake-based machines to give its customers time to "prepare for their Windows 10 upgrade".
Systems from this list of approved devices, which Microsoft will publish this week, will continue to receive support for Windows 7 and 8.1 until July 17, 2017. After July 2017, only the most critical Windows 7 and Windows 8.1 security updates will be released for these devices.
Windows 7 and 8.1 will also continue to be supported when running on older processors than those listed above - Windows 7 until January 14, 2020 and Windows 8.1 until January 10, 2023.
In his post, Myerson said the changes to hardware support were due to the complications of supporting older technology.
"Windows 7 was designed nearly 10 years ago before any x86/x64 SOCs existed.
"For Windows 7 to run on any modern silicon, device drivers and firmware need to emulate Windows 7's expectations for interrupt processing, bus support, and power states- which is challenging for WiFi, graphics, security, and more. As partners make customizations to legacy device drivers, services, and firmware settings, customers are likely to see regressions with Windows 7 ongoing servicing."
From the end of October 2016, PC makers will also have to sell new machines with Windows 10, rather than Windows 7 or 8.1. After that point businesses that want to run older Windows versions on new machines will have to rely on downgrade rights or software assurance rights under volume license agreements.
Microsoft has faced criticism for adopting aggressive tactics in pursuit of its goal to get Windows 10 onto one billion devices by 2018.
Most recently there was a backlash against Microsoft's plans to automatically begin upgrading most Windows 7 and 8.1 machines to Windows 10. The corporation also recently revealed that it would be pushing Get Windows 10 nag messages to a broader range of Windows 7 and 8.1 PCs, including network setups commonly used by small businesses.
User numbers for Windows 10 are growing and earlier this year Microsoft announced that more than 200 million devices worldwide were running Windows 10. Among businesses, Myerson said that more than 76 percent of enterprise customers were in "active pilots" and there were more than 22 million devices running Windows 10 across enterprise and education customers.
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- Launch a pilot program to work out Windows 10 wrinkles before you deploy(Tech Pro Research)