Microsoft has reported that the rollback of the impacting code change has completed successfully. All users who had been experiencing problems signing into Office 365 should now have success.

If you are still experiencing problems accessing Office 365 email, please contact the IT Support Centre for assistance.

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Previous Description (May 13, 2020 15:46):

Microsoft has reported that a recent change was responsible for the problem some users were experiencing when attempting to access Office 365 email. Microsoft has reverted the change and users are now beginning to report that the problem has been fixed and that they can now access Office 365 email.

It has also been determined that accessing Office 365 email via a web browser was primarily affected during this period. We have no reported problems from users who access email via a desktop client or from users that were accessing other Microsoft services.

It often takes a period of time for changes to propagate across Microsoft's infrastructure and IT Services will update this notification when Microsoft has confirmed that the fix has fully propagated.

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Previous Description (May 13, 2020 14:42):

Some users are reporting that they are unable to sign into Office 365 email. Some users are still able to login and use emails services without any degradation. IT Services is investigating to understand who may be impacted by this degradation. Please continue to report any access issues to the IT Support Centre via the online helpform to help determine the breadth of the issue via. https://www.queensu.ca/its/forms/itsc/helpform/

Workarounds:
There are no known workarounds at this time. As workarounds become available or if the problem is resolved, IT Services will update this notification.

IT Services has contacted Microsoft directly and they have provided an initial update as follows:

Users may encounter an error with the following message: "AADSTS50011: The reply URL specified in the request does not match the reply URLs configured for the application: 'e48d4214-364e-4731-b2b6-47dabf529218'".
Current status: Microsoft is collecting data on the application referenced in the error message and is investigating root cause.

Scope of impact: This issue may potentially affect any user, but is not reported as wide spread