Microsoft has blocked a number of security updates for some AMD based PCs after discovering that installing updates to combat the Spectre and Meltdown bugs left some devices unable to boot.
Microsoft said it will temporarily stop sending the nine systems updates out to some PCs running particular AMD processors.
"Microsoft has reports of customers with some AMD devices getting into an unbootable state after installing recent Windows operating system security updates," the company said.
"After investigating, Microsoft has determined that some AMD chipsets do not conform to the documentation previously provided to Microsoft to develop the Windows operating system mitigations to protect against the chipset vulnerabilities known as Spectre and Meltdown. To prevent AMD customers from getting into an unbootable state, Microsoft will temporarily pause sending the following Windows operating system updates to devices with impacted AMD processors at this time:
Microsoft said it is working with AMD to resolve this issue and resume Windows OS security updates to the affected AMD devices "as soon as possible", but said for AMD device-specific information users should contact AMD.
For AMD PCs stuck in an unbootable state after updating, Microsoft has provided some links that could help with the problem:
Yesterday ZDNet reported that Microsoft's Windows patch for the Meltdown and Spectre attack methods was causing problems for users with AMD Athlon CPUs, according to a number of complaints on Microsoft's community forum. One poster said after installing the update the PC only displayed the Windows logo and otherwise failed to boot. The update was delivered through Windows Update to a "quite pre-historic" computer, specifically running on the AMD Athlon X2 6000+, which was released a decade ago. Others who report the same issue are also using older AMD chips.
The Spectre and Meltdown flaws are critical vulnerabilities found in many Intel chips which could allow an attacker steal data from the memory of running apps, such as data from password managers, browsers, emails, and photos and documents. Since they were discovered the tech industry has been scrambling the fix them, and this problem is just one of the unexpected consequences.
AMD chips aren't vulnerable to the Meltdown attack, but operating system updates could address one of the Spectre attacks it was vulnerable to.
AMD said there was a "near zero risk" its chips could be exploited by the second Spectre attack, which required OEMs to issue firmware updates containing CPU fixes -- such as Intel's IBRS microcode fix or Google's Retpoline software fix.