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Security & privacy

Uh oh: Windows 10 update breaks your antivirus program

Here at, we frequently remind users to stay current with the latest updates for their respective operating systems. Not only does this put you at the cutting edge of new features and settings, but it also keeps your systems as secure as possible with the most recent patches and bug fixes.

While keeping your system up to date is critical, a glitchy update can make the entire endeavor seem pointless and ineffective. Microsoft is no stranger to bad updates, and despite its flaws, we’ve continued to insist that Windows users keep their computers current. The same, however, cannot be said for the latest Windows update.

Microsoft released an update to fix known CPU issues, and in the process has managed to break many commonly used features in Windows. Not only can this buggy update kill your Start Menu and search feature, but it even breaks the best protection your system has against hackers: Windows Defender. Here’s why we’re breaking tradition and advising Windows users to hold off on updating if they can help it.

A ‘software fix’ does just the opposite

Updated 09/19/2019: According to new reports from Forbes, the latest Windows update has caused issues with Windows Defender for multiple users. This is the built-in antimalware software that comes bundled with Windows and is the best line of defense against malicious software and hacking attacks.

Due to how dangerous using an unprotected computer online can be, we highly recommend users who updated Windows to patch their Windows Defender as soon as possible. For security reasons, Microsoft has already released an official patch to remedy this issue. Click or tap here to download it.

Microsoft released update KB4515384 in response to user reports of CPU activity spiking unnecessarily on Windows 10 computers, which created significant slowdowns and unexpected behavior. The patch, however, managed to break several of the most commonly used features in Windows 10 and caused an uproar online over Microsoft’s poor quality control.

If you download the KB4515384 update, you can expect things like your Start Menu or search function to start behaving oddly, or not work at all. Most notably, though, is the fact that users are experiencing issues with their computers connecting to the internet.

Reports to Microsoft’s feedback forum state that the update corrupts the drivers responsible for letting your computer talk with your networking accessories, including your ethernet ports and Wi-Fi antenna. As of now, there are no announced update plans from Microsoft, and it is unknown when a patch will be ready.

Am I affected? What can I do?

This defies our longstanding tradition of encouraging users to update their computers, but we would advise not updating to the latest version of Windows until Microsoft gives the all-clear for a new version of Windows 10. Any bug that knocks out internet connectivity is basically a non-starter in today’s hyper-connected world.

If you did manage to update your computer, or if Windows automatically updated for you, the good news is that some computers have the ability to roll back to a previous version.

To do this, navigate to your system’s Settings, click Update & security, and then select Recovery from the panel on the left. You should see an option to Go back to the previous version of Windows 10, which will roll back your system to its previous update.

Keep in mind, by doing this, you will lose whatever new things were put on your computer between then and now, so make sure to back up any precious information before continuing. The on-screen instructions will guide you through the rest.

Ironically, knocking your computer off the internet will keep your computer safer from hackers since they won’t be able to connect to your system in the first place! Of course, we highly doubt that was the update’s intention. But with how goofy Microsoft’s quality assurance has been, can we really be sure?

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