My windows defender is not working properly

Hi AzureAdmin,

One reason an unauthorized file might not be detected is if it is included in the antivirus (AV) exclusions. We do not recommend setting antivirus exclusions unless absolutely necessary. and here are some common mistakes to avoid.

Additionally, if your server is onboarded to Microsoft Defender for Endpoint (MDE), I suggest confirming the health status of your server on Defender. Any alerts generated would be a good starting point for troubleshooting.

In the event this is a false positive - Please follow the steps outlined here - https://learn.microsoft.com/en-us/defender-endpoint/defender-endpoint-false-positives-negatives

Finally, do raise a support ticket if further investigation is needed:

If none of this works, raising a support ticket is the recommended route. To Raise a support Ticket:

• Go to the Azure Portal.
• Click on the Help + support option in the left-hand menu.
• Select New support request.
• Follow the prompts to create a support ticket explaining your issue.

https://learn.microsoft.com/en-us/azure/azure-portal/supportability/how-to-create-azure-support-request

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