Microsoft Defender is the built-in anti-malware package that comes with modern Windows operating systems. It is alternatively known as Windows Security (it appears under Settings like Windows Security) or Windows Defender (sometimes with Antivirus at the end of the name, as on this Microsoft Docs page). But whatever you want to call it, for many Windows users, this tool is the standard for managing security on their PCs.
As with Windows Update in general, Microsoft Defender updates sometimes do not work. Defender updates are typically handled as part of routine Windows update behavior that is run on a daily basis as a scheduled task. But sometimes Windows Update even runs into problems and does not do much (or anything).
Should this happen, there are other ways to keep Defender up to date and avoid issues that are strictly related to the Windows Update itself. (See the note at the end of the story for more advice on this topic.)
Use Microsoft Defender’s own update feature
In the Settings app, you can access a Windows security facility with this selection sequence: Start> Settings> Update & Security> Windows Security in Windows 10 or Start> Settings> Privacy & Security> Windows Security in Windows 11. There you will find a button labeled “Open Windows Security” as shown in Figure 1. Alternatively, you can open the app directly by typing “Windows Security” in the Start menu.