Microsoft Security Essentials is a free antivirus software that is developed by Microsoft to protect computers against malware and other security threats.
However, users reported some issues with it, including the following:
* MSE will not start in Windows 8 and 10 – This issue seems to be caused by Windows Defender being enabled. To fix this issue, disable Windows Defender and restart your computer. * MSE won’t update – This problem is usually caused by outdated system files. To fix this error, run the Windows Update troubleshooter and check if that fixes the issue. * MSE won’t install – This issue is usually caused by an incompatible antivirus program. To fix this error, disable your antivirus program, restart your computer, and try installing MSE again. * MSE won’t update Windows Defender – This issue is usually caused by an outdated Windows Defender. To fix this error, run Windows Defender, click the Update button, and click Check for Updates.
- Microsoft Security Essentials is a freeware antivirus software that can protect your PC from viruses.
- This antivirus software will not install on Windows 7 or 8, but you can still get it working.
- Learn how to install Microsoft Security Essentials on Windows 7 in our latest article.
- Don’t hesitate to explore our complete Security Software Hub for more guides.
PC problems? Solve them in minutes.
Stop Windows Defender
- Press the Windows key + I to launch the Settings app.
- Navigate to the Update & Security section.
- Select the Windows Security option.
- Click on Open Windows Defender.
- Click Stop.
Use the Command prompt
Press Windows Key + X and select Command prompt (Admin).
When Command prompt starts, enter the following line and press Enter: sc delete MSASCui.exe
- Now enter the following command and press Enter: sc delete MSASCui.exe /f
- When Command prompt restarts, the Microsoft Security Essentials Update Service should no longer be running.
Run the SFC scan
- Press Windows + S to open the Search menu, enter cmd in the text field, and click on the relevant search result.
- Now, enter sfc /scannow in the Command prompt text box, and press the OK button.
Run the DISM
- Press Windows Key + S and enter DISM. Select the first result.
- Select Microsoft-Windows-Deployment-Manager from the list.
- Press the Continue button.
- Now, select Deployment Image Servicing and press the Continue button.
- In the DISM window, press the Browse button.
- Locate the dism-windows-8.1-amd64-en-us.msu file and click Open.
- Press the Next button and wait for the process to finish.
Perform a Clean Boot
- Press Windows + R to open Run, type msconfig, and click OK.
- Select the Services tab, and uncheck the Hide all Microsoft services box.
- Select the Startup tab, click the Open Task Manager button, right-click on Microsoft Security Essentials, and select Disable.
- Finally, click OK and restart the desktop or laptop.
- Manually Update Microsoft Security Essentials
Run the System Update troubleshooter
- To do that, press the Windows key + I, select Update & Security, and then Troubleshoot.
- Next, select Other troubleshooters and pick the Windows defender troubleshooter.
- Lastly, click the Run the troubleshooter button.
Install Windows Defender as an administrator
- Open the Start Menu and type Windows Defender -> select Windows Defender Security Center in the search results.
- Click on Turn Windows Defender On or Off -> click on On at the top.
- Next, click on Yes when prompted.
- Now, make sure Windows Defender is set as the default antivirus program.
Modify the User Account Control settings
- Press Windows Key + R to open Run.
- Type in “regedit” and click OK to open Registry Editor.
- Navigate to the following key:
- Create the following DWORD value:
- Double-click on the value to open its properties.
- Set the value to 1.