Add users (members) to Azure Active Directory that isn't of a verified domain name in the directory

Question

When I try to add a user with a login that's a regular email address like john@gmail.com, I have the following message on the right:

'gmail.com' is not a verified domain name in this directory

I want them to be able to authenticate without a name like 'john@MyApp.onmicrosoft.com'. I read an answer that said this isn't possible, but I can see gmail and outlook email addresses that someone else added (they aren't around). They are members, not guests. How do you add users like that?

Answer 1

Add Guest User is the button you are looking for.

It allows you to add users with any email address.