Check if Microsoft Windows Defender does not start on Windows 10 issue still occurs. Method 9: Reset PC This is considered to be the last resort when the above mentioned fails to fix the issue.

Fix Windows Defender Error code: 0x8050800c, An unexpected problem occurred, Install any available updates, and then try to start the program again.

If Windows Defender Error 1297 occurs when you try to open it or run a scan on Windows 11/10, use the fixes in this post to resolve the issue.

Arguably, Microsoft jumped the gun with Windows 11, which had its share of issues and bugs at launch. Here's how to fix the most common issues with the OS.

Microsoft has admitted that the Windows 11 security issue, wherein Defender would wrongly display LSA protection is disabled, isn't really fixed. The company has provided the same workaround.

The August 2024 Windows Server updates fix a known issue that breaks multiple Microsoft 365 Defender features after installing last month's security updates.