Windows 10: Windows Defender continues to run in background after installing third party security software

I have a new PC running Windows 11 Pro. After completing all Windows updates, I installed Norton 360, but then noticed that a lot of RAM was being used. I opened task manager and saw that Antimalware Service Executable was still running in the background.It was my understanding that that once a third party security software was installed, all components of Windows Security should no longer be running. I contacted Norton, which was not of much help, and they indicated the problem as with Windows.Not content with that answer, I completely removed Norton and installed two other third party securi

:)

 

Windows defender's process running despite it being disabled.

Windows Defender is integrated within Windows 10. So you have it and it is running (as it should be) unless you installed a 3rd party "real-time" anti-malware solution. If you are using an alternative security solution, it should have registered itself with Windows Action Center which would then disable the real-time component of Windows Defender - unless you specifically told the 3rd party solution not to register itself.

For example, if you purchased Malwarebytes "Premium", it has a real-time scanner (the free version does not). When you install Malwarebytes Premium, it registers itself in Windows Action Center. But because Malwarebytes and Windows Defender play very well together without hogging resources or causing conflicts, it is often recommended to allow each to run at the same time. So to allow that, the user has to manually go into the Malwarebytes control panel Settings menu and select the option to "Never register Malwarebytes in the Windows Action Center".

I suspect other 3rd party solutions provide similar options so you might check that out if you did indeed, install a 3rd party security solution.

Both Windows Update and Windows Defender are supposed to step way back in to the background so they do not interfere with system performance when you are actively using your computer. But this is not always possible, especially if you regularly shut down your computer when you step away from it (instead of just letting it go to sleep), as too much time may have passed and your system is too far behind in Windows and security updates.

Without you noting which program was actually consuming the lion's share of that 80%, there's no way to tell what, at this point, was causing the problem. However, I would not put it past a browser. Chrome, for example, is very good (or bad, I should say) at eating up a lot of RAM and failing to let it go when exited.

 

Windows Defender seems to be running constantly

Hi Jeff,

Windows Defender Antivirus helps protect your PC against malware (malicious software) like viruses, spyware, and other potentially unwanted software. It is also providing real-time protection when malware tries to install itself
or run on your PC. That’s why it is always running in the background if you check the Task Manager.

If you want to temporarily turn off Windows Defender Antivirus, follow these steps:

• Click the Start button, then type
  Windows Defender Security Center.
• Open Windows Defender Security Center, then select
  Virus & threat protection > Threat settings.
• Turn off Real-time protection.

Note:

• If you temporarily turn off the Windows Defender Antivirus, your device may be vulnerable to threats.
  
• Scheduled scans will continue to run. However, files that are downloaded or installed will not be scanned.
  

Let us know how it goes.

 

windows defender

Hi Nishitha,

If you have another antivirus app installed, Windows Defender will turn off automatically. Are you running a third-party antivirus software?

If you're not running a third-party antivirus software, you may turn Windows Defender real-time protection on by following these steps:

• Select the Start button, then select Settings
  > Update & Security.
• Select Windows Defender, then turn Real-time protection on.

Let us know if you need further assistance.