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In order to better secure University staff Raven accounts, UIS is turning on has enabled Multi Factor Authentication (MFA) to all Raven accounts by 1 October 2021. This means that when you go to use your Raven account for certain Microsoft applications you will need to confirm your log in using another device. Typically this is done by using the Microsoft Authenticator app on a mobile phone (note that there are other options if this doesn't work for you).
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https://help.uis.cam.ac.uk/service/accounts-passwords/multi-factor-authentication/managing-mfa
Support
As CSCS is not involved in the setup or maintenance of MFA, please contact the UIS' dedicated support desk for assistance staff and students with any MFA-related queries. You can reach them at https://mfahelp.uis.cam.ac.uk which will be available 24/7 during the initial rollout ending 1 October 2021.