Additional Microsoft Defender tools and services that provide security across various platforms and environments
If the cloud-delivered protection test file downloads and opens instead of being detected and removed, cloud-delivered protection is not working correctly on that device.
Use this check path:
- Verify Microsoft Defender Antivirus settings:
- Open Start > Settings > Update & Security > Windows Security > Virus & threat protection.
- Select Manage settings.
- Confirm these are turned On:
- Cloud-delivered protection
- Automatic sample submission
- Confirm real-time protection is enabled.
- The test requires Microsoft Defender real-time protection to be on.
- Update Defender before testing again:
- Open Windows Security > Virus & threat protection.
- Under Virus & threat protection updates, select Check for updates.
- Under Threat definitions, select Check for updates.
- Run the Microsoft cloud-delivered protection test again.
- The test file is harmless and is designed to simulate malware detection.
- Expected result: Microsoft Defender Antivirus should detect the file, show a warning, and delete or quarantine it.
- Check whether the detection was recorded:
- Open Windows Security.
- Go to Virus & threat protection > Protection history.
- Under Quarantined threats, select See full history.
- A successful test can also appear in the Windows event log as Microsoft Defender Antivirus event ID 1116.
- If the file still executes or is only blocked by SmartScreen, validate Defender network connectivity.
- Microsoft states that if the file executes, or if only Microsoft Defender SmartScreen blocks it, cloud-delivered protection is not working.
- In that case, use the Microsoft Defender Antivirus network connection validation guidance.
- If downloaded files are being blocked or warned on by Windows itself, check whether Attachment Manager or SmartScreen is involved.
- In File Explorer, right-click the file > Properties.
- On the General tab, check for a security message such as the file being blocked because it came from another computer.
- In Microsoft Edge, check Settings and more (...) > Settings > Privacy, search, and services > Security and verify Microsoft Defender SmartScreen is on.
- Turning off SmartScreen makes the device more vulnerable.
If suspicious files are still not detected after those checks, submit the file to Microsoft for analysis.