My windows security app is not working.

Question

i recently tried to download a game from firgirl website. When I unzipped the file and tried to run the setup, it was keep on giving me error. My windows security was keep on blocking that file. But than I deactivated all firewalls and realtime scanning and protection from virus and tried to download the game. But it ended up not being download. Now I deleted the game but my system seems to have affected my a virus. My windows security app is not working at all. Do help me go through this issue. I checked your articles, but nothing seems to help.

Answer 1

Hi Shayan,

The Microsoft Defender Antivirus service may have been deleted by that game app. Before repairing Microsoft Defender Antivirus and the Windows Security app, infection needs to be removed. Please download Malwarebytes Antimalware and run a scan. Eliminate every piece of malware it finds. Malwarebytes should also get rid of all adware and PUAs and browser hijackers.

https://www.malwarebytes.com/mwb-download/thankyou

Note: the Malwarebytes setup may activate the Premium trial (15-day) version. After 15 days, it switches to the free version automatically.

Post the detection report here.

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Standard Disclaimer: There is a link to a non-Microsoft website. The page appears to provide accurate, safe information.

Answer 2

Follow these steps in order to try to recover Windows Security and clean the device.

1. Run a quick malware scan
   • Open the Windows Security app.
   • Go to Virus & threat protection > Quick scan or use this shortcut: Start a quick scan.
   • If threats are found, follow the on‑screen actions to remove or quarantine them.
2. Turn real-time protection back on
   • In Windows Security, go to Virus & threat protection > Manage settings or use this shortcut: Virus & threat protection settings.
   • Make sure Real-time protection is turned On.
   • If it is off and cannot be turned on, proceed to step 3.
3. If Windows Security features are misconfigured
   • Download and run the Windows Security Troubleshooter on the affected PC:
     • Select Download on this page: Automatically fix Windows security issues (from the context).
     • In the File Download dialog, choose Run or Open and follow the steps.
   • This troubleshooter checks and enables key security features such as:
     • Microsoft Defender Antivirus status and updates
     • Windows Firewall
     • SmartScreen/Phishing filter
     • User Account Control (UAC)
     • Data Execution Prevention (DEP)
4. If Windows Security still does not work or malware persists
   • Uninstall any unknown or unwanted software:
     • Go to Settings > Apps > Apps & features and remove software that is not recognized or is no longer needed.
   • Update Microsoft Defender Antivirus definitions and run a full scan from Windows Security.
   • If unwanted software remains, perform an offline scan with Microsoft Defender Offline as described in Protect your PC from unwanted software.
5. If downloads are being blocked going forward
   • If Edge or security features block downloads that are believed to be safe, use the guidance under Report a download you believe has been incorrectly flagged in the same article to report a false positive. Do not disable protection permanently.

If Windows Security still does not open or function after these steps, backing up important data and performing a repair install or reset of Windows may be required, but that is not covered in the provided context.

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References:

• Stay Protected With the Windows Security App
• Automatically fix Windows security issues
• Protect your PC from unwanted software