To avoid mail flow disruption between your organization and Exchange Online, organizations that send or receive email to or from Exchange Online must ensure that their servers and clients trust the D...
Updated Jan 30, 2026
Version 2.0
Blog Post
5 MIN READ
Trust DigiCert Global Root G2 Certificate Authority to Avoid Exchange Online Email Disruption
Nino_Bilic
Microsoft
MicrosoftCorrect.
Again - as far as we are aware, most of our customers never disable Windows CTL Updater and so they will not have any issues. But we have to basically let everyone know about this change because there are customers who do, or have 3rd party appliances etc. that might need work.
Nino_Bilic 3rd party email gateway only? or Firewall\ASA devices as well?
Also, since I see certificate on Exchange on-premise servers I should not be worry about email disruption ? of-course I will check with team who manages 3rd party email appliances, but Do I need to check anything else except Exchange server and 3rd party email appliances ?
- Arindam_Thokder
Pankaj_Messaging_Specialist - Any appliance that actually establishes SMTP session with Exchange Online and checks for certificate validity, if it a firewall, then that as well. Think of it this way: if you have a client that directly connect to Exchange Online to send a TLS encrypted message, it might be impacted.
