If you are happily running Windows 11 on your personal computer you may want to take note of the latest warning from Microsoft. The Windows creator has issued a fresh warning to PC users about a new bug that could stop Windows 11 from installing vital security updates.

As spotted by Bleeping Computer, Microsoft has spotted a problem where after installing Windows 11 version 24H2 the system doesn’t allow you to install any subsequent security updates. Leaving your machine in this state would leave you open to worrying security flaws down the line.

“When using media to install Windows 11, version 24H2, the device might remain in a state where it cannot accept further Windows security updates”, Microsoft said on its known issues page for Windows 11.

“This occurs only when the media is created to include the October 2024, or November 2024, security updates as part of the installation (these updates were released between October 8, 2024 and November 12, 2024).”

The firm goes on to note this error only occurs if you are using a CD or USB flash drive to install the latest software version, which is increasingly rare among PC users, who are more likely to download the latest free Windows 11 updates online. The bug also only affects versions of Windows 11 being installed with security updates released between 8 October and 12 November.

Still, for Microsoft to put out a statement on the problem is noteworthy. It’s still common for professional or Windows users who’ve built their own desktop PCs to update Windows using physical media installs, so the issue seems widespread enough to have caused strife for Windows 11 devotees worldwide.

If you’ve found yourself installing one of the dodgy updates via these means, the bad news is that Microsoft currently doesn’t have a fix.

“We are working on a resolution and will provide more information when it is available,” the firm said.

If you have caught this news just in time, Microsoft advises to install Windows 11, version 24H2 with the latest December 2024 monthly security update - not the October or November versions - to avoid the bug that prevents future updates from being installed.