Microsoft 365 Alert : Service Degradation – Exchange Online – Recipients are unable to open encrypted email messages sent via Exchange Online – RESOLVED
06/01/2022 08:02:00 AM (GMT)
Issue Reported : 17/12/2021 07:28:00 AM (UTC)
Microsoft Reference : EX311826
Issue Status: RESTORED
Issue Description: Recipients are unable to open encrypted email messages sent via Exchange Online.
More info: Affected users may use a One Time Password (OTP) as an alternative method to open encrypted email messages.
Scope of impact: The issue may impact any users sending external encrypted email messages.
Final Update – 06/01/2022 08:02:00 AM: Microsoft is investigating why the compatibility issue with the Outlook on the web legacy codebase was causing message decryption failures to prevent this problem from happening again in the future. They have confirmed the issue resolved.