High cpu and memory usage on antimalware service executable

Tiago Machado 0 Reputation points
2025-07-22T14:18:12.9233333+00:00

Hi, in the last 2 days i been having all the time high cpu and ram usage by the antimalware service executable, im gonna post a screenshot on task manager so you can see it.
Ram usage has been between 11gb to 3gb and processor usage 20% to 40%.
This started to happen 2 days ago and i didnt open shady stuf or downloaded it.
This pc has 2 weeks and it was running great whit everything uptaded and every driver updated.
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Saw a couple of post about this and i have tried :
Press Windows key + R. This will open Run. Alternatively, you can go to Start and search for Run.

  1. In Run dialog box, type taskschd.msc and hit enter.
  2. Navigate to Task Scheduler Library > Microsoft > Windows > Windows Defender.
  3. On the right hand pane, double-click on Windows Defender Scheduled Scan.
  4. On the General tab, uncheck the option Run with highest privileges.
  5. Click on Conditions tab and uncheck all the options.
  6. Click on OK.

Open Microsoft/Windows Defender.

  1. Click on Virus & threat protection > Virus & threat protection settings.
  2. Locate 'Exclusions' and click Add or remove exclusions.
  3. Hit Add an exclusion and select Process in drop down.

In Add an exclusion, type MsMpEng.exe and click Add.

Dont know any other fix, my system specs are :

  • Ryzen 7 7800x3d
  • RX 9070 XT
  • 32gb ddr5 6000mhz

Thanks for any help.
Best regards, Tiago.

Microsoft Security | Microsoft Defender | Microsoft Defender for Identity
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  1. Catherine Kyalo 2,695 Reputation points Microsoft Employee
    2025-11-25T13:49:25.36+00:00

    Tiago Machado,

    High CPU (20–40%) and RAM (up to 11 GB) usage by Antimalware Service Executable (MsMpEng.exe), which is the core process for Microsoft Defender Antivirus. This spike usually happens during real-time protection scans, scheduled full scans, or when Defender repeatedly scans large or complex files. Here’s a guide on further troubleshooting https://v4.hkg1.meaqua.org/en-us/defender-endpoint/troubleshoot-performance-issues

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