I'm cloning the D8 issue https://www.drupal.org/project/openid_connect_windows_aad/issues/2930510 → so the port in comment #6 can be ported to D7 as I've just run into the same issue now.
Throughout the openid_connect module, the user's mail mapping uses $userinfo['email']. However, the returned user's info object in the integration with Azure uses $userinfo['mail'].
The patch that ended up being applied and released to the D8 version simply replaces 'email' with 'mail', and then makes sure it creates a new item in the array for 'email' as well so the openid_connect module can continue using it.
Closed: won't fix
1.0
Code
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