Is it safe to remove Windows Defender? [duplicate]

Question

I've recently been rather fed up with Windows, and have started removing useless system apps like Edge & IE, and I constantly see Windows Defender using 30+% of my CPU.

I have another antivirus. A better antivirus, so that's no issue. The only thing I'm worried about is whether or not Windows will stably work if I remove Windows Defender. I have heard news of Windows seemingly "breaking" when removing core packages.

Is it safe to remove defender? Will Windows functionality be hindered by the removal?

EDIT: This question is not about how to remove Windows Defender.

Why do so many users assume the question is "how to remove?", while it's "is it safe?"

Answer 1

Windows Defender has had a history of not playing perfectly nicely with other antivirus installed - they can start arguing over who should scan a file, or if one scans it the other notices and triggers the on access scanner - back and forth for a while wasting resources. To be fair, installing any two virus scanners at the same time with real time or on access scanning will likely give this behaviour. Full system scans could also use a lot of CPU and disk activity (which is why I recommend using only on access scanning).

I've not seen any descriptions of removing Windows Defender entirely. If there are certain files that could be deleted, I don't know them.

When you install another antivirus, Windows Defender should automatically be disabled:

Starting with the Windows 10 Anniversary Update in the Summer of 2016, Windows Defender can actually run alongside another antivirus app. When you install another app, Windows Defender itself isn’t disabled—just its real-time protection component is. That means your third-party app handles real-time protection, but you can still run a manual scan with Defender whenever you want.

https://www.howtogeek.com/howto/15788/how-to-uninstall-disable-and-remove-windows-defender.-also-how-turn-it-off/

To disable on access scanning manually, Microsoft says

1. Open Windows Defender Security Center, then select Virus & threat protection > Threat settings.
2. Turn off Real-time protection. Note: Scheduled scans will continue to run. However, files that are downloaded or installed will not be scanned.

If you find it re-enables itself, methods for keeping it turned off more permanently include:

Open Regedit and browse to

HKEY_LOCAL_MACHINE > SOFTWARE > Policies > Microsoft > Windows Defender

Create or edit a key called 'DisableAntiSpyware' to have the value '1'.

Or, if you have a Pro or Enteprise edition of Windows:

Press the “Windows key + R” to load the Run box, then type gpedit.msc into the box and press OK to get the group policy editor. Then browse to

Computer Configuration > Administrative Templates> Windows Components > Windows Defender

Open the “Turn off Windows Defender” policy, and enable it.

Answer 2

If disabling Windows Defender is sufficient, you can do this by emulating the registry entry that group policy editor uses to disable it. Run regedit and navigate to:

HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows Defender

Create a DWORD entry called "DisableAntiSpyware" and set it to 1. When you reboot, the Windows Defender service will be stopped. Indeed, after this, even trying to manually start the service will fail, so remember where you parked, so to speak, if you want to undo this later.

Answer 3

This depends, are you referring to system stability, malicious programs or other points.

To remove Windows Defender, first download win6x Registry Tweak and run the following from an elevated command prompt:

install_wim_tweak.exe /o /c Windows-Defender /r

More topics:

• How to disable Windows Defender on Windows 10
• How to turn off Windows Defender permanently