Exactly. this is such a pain, especially if you happen to be apart of one organization that's AAD Connect and one that's full AAD (Azure Active Directory). As

Exactly. this is such a pain, especially if you happen to be apart of one organization that's AAD Connect and one that's full AAD (Azure Active Directory). As far as I can tell, the easiest way to switch users is to go to https://www.office.com/login?es=Click https://www.office.com/login?es=Click directly (?es=Click is important) which will present you with all the accounts you're 'Signed in' with, even if office.com has you locked into one. Then you can use the app switcher to switch domains, which ensures the correct account.