Forum Discussion
Sensitivity label "Certificate Error"
When applying Sensitivity Labels in Microsoft Office applications, we receive the following certificate warning:
"The certificate issuer for this site is untrusted or unknown. Do you wish to proceed?"
We have already excluded the required Microsoft Azure URLs from the firewall and disabled SSL/TLS inspection, but the issue still persists.
Observations:
1.On the same domain-joined computer, when signed in with a local user account, Sensitivity Labels work correctly without any errors.
2.When signed in with a domain user account, the certificate warning appears while applying or accessing Sensitivity Labels.
Could you please help us identify the root cause and provide a solution? Your assistance in troubleshooting this issue would be greatly appreciated.
1 Reply
Since the issue occurs only for domain users on the same machine, the problem is likely within the user context (Current User certificate store, GPO-applied certificates, cached RMS/MSIP credentials, or proxy settings) rather than network connectivity.
Before making changes, please click View Certificate on the warning dialog and provide:
- Certificate Subject
- Certificate Issuer
- Certification Path
- Thumbprint
Also compare the Current User certificate stores between:
- Working local account
- Affected domain account
Particular attention should be given to:
- Trusted Root Certification Authorities
- Intermediate Certification Authorities
- Personal Certificates
If the issuer differs between the working and failing account, that will usually identify whether the certificate is being injected by a GPO, security product, proxy, or whether there is a trust-chain issue in the user's profile.
My answers are voluntary and without guarantee!
Hope this will help you.
