Suddenly getting Edge WebView2 firewall access requests on endpoints

Question

A few weeks ago our endpoints started getting firewall prompts to allow Edge WebView2 through - this is the version that Teams is using. Why are we getting these all of a sudden and how do we stop them for end users?

I can allow the application through using Intune security profiles however the executable that's being called is in a directory of the version so any time the version changes, the rule needs to be changed.

Answer 1

Dear @Marc,

Thank you for reaching out to Microsoft Q&A forum.

I understand you’re experiencing unexpected firewall prompts for Edge WebView2, which is disrupting your work. The issue is likely a result of a recent Microsoft Teams or Edge WebView2 Runtime update that changed the application's network signing, execution path, or the underlying protocol it uses for communication, which invalidated your existing Windows Firewall rules.

From my research, the Edge WebView2 Runtime is a component that allows modern Microsoft 365 apps (like the New Teams) to render web content. The New Teams client relies heavily on WebView2. A recent Teams update (which often includes an updated WebView2 Runtime) or the full rollout of the New Teams client may have:

• Changed Network Signatures: Even a minor patch can alter the security signature or hash of the executable, causing the firewall to treat the application as "new" and prompt the user for permission.
• Switched Protocols: An update might have shifted how the client connects (e.g., from using one port/protocol to another), triggering a firewall re-evaluation.

Version-Based Execution Path: As you noted, the executable is often located in a version-specific directory because the path contains the version number, any update that changes the current or version folder invalidates a firewall rule based on the full path.

As a forum moderator, I genuinely wish I could directly access your account or delve into the backend systems to diagnose and fix this for you. However, our role here is limited to providing general guidance and solutions that can be applied by users.  

For problems of this nature, I recommend that the Global Admin in your organization create a service request with Microsoft Support. A technical support engineer can perform a remote session to investigate the situation, verify the backend configurations, and run any necessary synchronization tools to resolve the problem. If the issue requires further attention, they can escalate it to a specialized team for deeper analysis. Ask The Global Admin in your organization to create a service request with Microsoft support to get advanced technical assistance and diagnostics. For detailed instructions on how to get support, please refer to Get support - Microsoft 365 admin. If you don't know who your IT administrator is, please refer to this article: How do I find my Microsoft 365 admin? - Microsoft Support 

For additional assistance, use this link to find the appropriate contact number: Global Customer Service phone numbers - Microsoft Support 

I truly hope you get your issue resolved swiftly. Please know that even though I can't directly intervene, directing you to the correct, specialized support is the most effective help I can provide from my position. Thank you for your patience and understanding. I'm looking forward to your reply.  

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