Facing Not Secure issue on Chrome when trying to use Azure Front Door custom domain

Hi @QA Test - welcome to the Microsoft Azure community.

Most likely the issue is not Chrome or Front Door, but an incomplete certificate chain that Chrome is exposing.

If you uploaded the GoDaddy certificate to Front Door, the full chain is required. From Configure HTTPS: “your certificate must have a complete certificate chain with leaf and intermediate certificates. The root CA also must be part of the Microsoft Trusted CA List.” Domains adds: “Front Door serves the certificate chain that you provide, so the uploaded chain must terminate at the intended trusted root” and warns that “If a certificate without complete chain is presented, the requests that involve that certificate aren’t guaranteed to work as expected.”

Browsers disagreeing is expected here. Troubleshoot common issues notes: “The browser rebuilds the certificate chain of trust to be what it thinks it should be instead of showing exactly what the origin server returned.” That also explains why going directly to the firewall looks fine.

To see what Front Door is actually serving:

openssl s_client -connect <your-custom-domain>:443 -servername <your-custom-domain>

If only the leaf certificate appears, re-upload the GoDaddy certificate with the intermediate included and the chain terminating at a trusted root. If the full chain appears, it would help to know whether Chrome shows a full interstitial or only “Not Secure” in the address bar, because those point to different causes.

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