Microsoft periodically refreshes certificates in Office 365 as part of their effort to maintain a highly available and secure environment. From Jan 23rd, 2021, Microsoft is making a certificate change on our Microsoft Federation Gateway every six weeks that could affect some customers
Who is affected?
This certificate change can affect any customer that is using the Microsoft Federation Gateway. If you are in a hybrid configuration or if you are sharing free/busy information between two different on-premises organizations using the Microsoft Federation Gateway as a trust broker, you need to take action.
What action should you take?
You can use the following command on your Exchange Server to create a scheduled task to run the update process daily. This is how we recommend you keep your Federation Trust constantly updated. This will prevent you from being negatively affected by future metadata changes.
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