Whatever the reason, you can disable Microsoft Defender Antivirus on your Windows 11 PC using any of the following methods. However, before you do that, you need to disable Tamper Protection first.

If you trust the app, you can temporarily turn off the SmartScreen Filter to install and run it, then turn it back on in the Windows Security settings.

This is a security feature where the OS is trying to authenticate the action. If you wish to turn off this Windows Security Making sure it’s you, this post will show you how to do it.