Software⏱️ 3 min read📅 2026-05-26

How to Fix: Is it risky to install? " Windows protected your PC" , "Microsoft Defender

Unknown publisher, potentially risky installation, exercise caution.


The error message 'Windows protected your PC, Microsoft Defender SmartScreen prevented an unrecognised app from starting' indicates that the Windows Complete Guide">operating system has detected a potentially malicious application. This is a built-in security feature designed to protect your computer from downloading and installing software that may pose a risk to its security.

⚠️ Common Causes

  • Unknown or untrusted publishers
  • Unrecognized application signatures
  • Outdated or malicious software

🛠️ Step-by-Step Verified Fixes

Method 1: Allow App from Publisher

  1. Step 1: Click on the 'Allow' button to permit the application to run.
  2. Step 2: If prompted, click 'Yes' to confirm the action.

Method 2: Update Microsoft Defender SmartScreen

  1. Step 1: Open the Settings app on your Windows device.
  2. System > Security & Update > Windows Security
  3. Update & Security > Virus & Threat Protection
  4. Manage settings for SmartScreen
  5. Update now

Method 3: Ignore the Warning (Not Recommended)

  1. Step 1: Click on the 'Ignore' button to dismiss the warning.
  2. Caution: Ignoring this warning may expose your device to potential security risks.

💡 Conclusion

To ensure the safety of your computer, it is recommended to allow the application from its publisher or update Microsoft Defender SmartScreen. Ignoring this warning may not be the best course of action.

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