Unfortunately, Microsoft Purview doesn't currently have a built-in feature to directly alert you when a file is shared externally. However, you can leverage a combination of Microsoft 365. To get an alert when a file is shared externally using Microsoft Purview, you need to set up Data Loss Prevention (DLP) policies and/or Audit Logs.
Here’s the process to set up alerts for when a file is shared externally:
- Access the Microsoft Purview compliance portal - Sign in at compliance portal.
- Navigate to Alert Policies - In the navigation pane, go to Policies, then select Alert policies.
- Create a Custom Alert Policy - You can create a new alert policy that specifically targets external sharing. For example, you can set a notification to alert you if someone shares a sensitive file externally.
- Configure the Policy - Specify the conditions under which the alert should be triggered, such as when a file is shared with external users.
- Review Alerts - You can view your alerts in the Microsoft Purview compliance portal under Policies > Alert > Alert policies.
For more details, please refer the below documentations:
I hope this information helps, please do let us know if you have any further queries.
Thank you.