I have a problem relating to this. I'm using Azure authentication (sk172909) which works a treat - BUT - I need to put in a proxy bypass for login.microsoftonline.com for this to work.
When I bypass login.microsoftonline.com then Outlook will no longer log in to O365. I guess some parts of the login going via the proxy and some parts not makes it break.
So I'm stuck between a rock and a hard place now.
I found sk116604 which is supposed to disable proxy settings for Endpoint, but this doesn't work either 😞
Has anyone else found a way around this yet?