If Windows Security (Microsoft Defender) throws Error 8024402f, Protection definition update failed on Windows 11, then follow this post to successfully fix the issue.

If you are not able to open Windows Security & you see error: Cannot Open this app, Your IT administrator has disabled Windows Security, see this post.

Users may see a 0x800f0922 error when trying to install security update KB5012170 on the currently supported Windows operating system for consumers and the enterprise ...

On Windows 11 (and 10), if the Windows Security app isn't working, you can reset it in multiple ways to resolve the most common issues, and in this guide, I'll explain how.

Security update KB5058405 for Windows 11 23H2 and 22H2 comes with severe side effects for some PCs. Microsoft's emergency patch fixes it.

Incorrect error messages seem to be a pattern for the company's latest operating system updates.