Forum Discussion
Outlook - Certificate has been revoked
If you're having certificate warnings in Outlook for an on-prem Exchange deployment you should post a screenshot here so we can see exactly what the warning says. There's a number of potential problems and solutions for certificate issues.
Here is the error message (Office 365):
Amir Jafarian that looks like either a problem communicating with the CRL or there might be another issue with your system or an intermediate network device (like a proxy). Since you are connecting to Exchange Online you can raise a support ticket with Microsoft for troubleshooting assistance. You can also try running diagnostics with the SARA tool (https://diagnostics.outlook.com).
Other posters are complaining of certificate popups for on-premises Exchange server environments, which could be an entirely different problem with their server or certificate configuration.
Hi,
We're experiencing the same issue as @Amir Jafarian
Fully patched msi version of Outlook 2016. Connecting to Exchange online. Sporadic Digicert certificate warnings across the org. Seems to happen most commonly when waking a device from sleep. I'd agree it looks like issues checking the CRL but can't find the cause.
We've got tickets open with Microsoft and our proxy vendor but not getting anywhere fast. We've had our proxy solution in place for some time without issue and nothing has changed.
I'll post if we find anything.
Can this be related to this?
I see addition of http://crl4.digicert.com/DigiCertCloudServicesCA-1-g1.crl in Office 365 Certificate Revocation List (Root URLs)
