Microsoft Corporation•Usually safe
wsappxWhat is wsappx?
wsappx is a legitimate Windows process from Microsoft that helps install, update, and manage apps from the Microsoft Store. If you found it in Task Ma...
MsMpEng.exeSafeWhat is MsMpEng.exe?
Publisher: Microsoft CorporationTypical location:
C:\Program Files\Windows Defender\MsMpEng.exeMsMpEng.exe is the Antimalware Service Executable for Microsoft Defender Antivirus on Windows. It is a legitimate Microsoft security process that helps protect your PC from viruses, spyware, and other threats.
What it does
This process runs in the background to scan files, monitor activity in real time, and help block malware before it can run. It may use more CPU, disk, or memory during full scans, updates, or when Windows is checking many files at once.
Is it safe?
Yes, the real MsMpEng.exe is safe and part of Windows security. However, malware can sometimes disguise itself using this same name. To confirm it is genuine, check that the file is signed by Microsoft Corporation and located in a Microsoft/Windows Defender folder, not a random or temporary directory.
Why it causes high CPU or disk usage
- 1Running a scheduled or full malware scan
- 2Scanning many new or changed files
- 3Windows Defender definition updates
- 4Conflicts with another antivirus or security tool
- 5A corrupted file that is being scanned repeatedly
How to check if it's legitimate
- Open Task Manager, find MsMpEng.exe, and right-click it.
- Select Open file location.
- Confirm the file is in a Microsoft/Windows Defender folder, not in Downloads, Temp, AppData, or another unusual location.
- Right-click the file, choose Properties, and check the Digital Signatures tab for Microsoft Corporation.
- If the location or publisher looks wrong, run a full malware scan immediately.
How to remove it
You should not remove the real MsMpEng.exe, because it is part of Microsoft Defender and helps protect Windows. If it is using too many resources, let the current scan finish, restart your PC, make sure Windows is up to date, and remove any other antivirus tools that may be competing with Defender. If the file is in an unexpected location or has no Microsoft signature, treat it as suspicious and scan for malware.
Recommended fixes
Restart your device
A restart clears temporary state that often causes transient errors.
- Save your work and close open apps.
- Restart the device from the power menu.
- Reproduce the issue to check whether it persists.
Install Windows updates
- Open Settings > Windows Update.
- Click Check for updates and install everything available.
- Restart if prompted.
Close resource-heavy apps
- On Windows open Task Manager (Ctrl+Shift+Esc); on macOS open Activity Monitor.
- Sort by CPU or memory usage.
- Quit apps you don't need that are using excessive resources.
Scan for malware (Windows)
- Open Windows Security > Virus & threat protection.
- Run a Full scan.
- Quarantine or remove anything detected, then restart.
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