Microsoft is aware and is working on the issue. They have provided us a work around to use. IT Services has implemented the fix.
If users are still experiencing the issue after clearing their browser cache this afternoon, (Mon, May 11th) they should contact the IT Support Center - 36666 to report.
ITS has restarted the ADFS login servers and contacted Microsoft for further assistance. Most users are able to login after clearing the browser cache or if that fails, trying another browser.
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Previous Description (2015-05-08 11:09:17):
ITS is investigating an issue with logins to Office 365 (Email, calendar and OneDrive services) where the login process is caught in a loop between the Queen's login page and Microsoft's. Clearing the browser cache has helped some users.