UPDATE 3/16/2026: We worked with the partner team to republish the Microsoft 365 Root Certificate Chain Bundles for Worldwide (WWMT) and GCC High / DoD (ITAR) after identifying that the previously pu...
Updated Mar 16, 2026
Version 11.0
Blog Post
6 MIN READ
Trust DigiCert Global Root G2 Certificate Authority to Avoid Exchange Online Email Disruption
We’ve completed the recommended validations on our side:
- Windows CTL Updater is set to Not Configured (default).
- Get-ChildItem results match exactly as shown in the blog.
- Last Sync status for both AuthRoot and Disallowed stores is up to date.
From our environment perspective, everything appears aligned.
For context, our mail flow uses on‑prem Exchange as the relay point for application traffic to Exchange Online, and we have Proofpoint deployed as our cloud email security gateway.
Please let us know if there are any additional checks or validations we should perform.
- Arindam_Thokder
Microsoft
Mani333 - You should be covered. Just check with Proofpoint once, if they do any certificate validation and if yes, it should trust DigiCert Global Root G2 Certificate
