We have remote sites with different domains on each site. We are looking at moving to cloud directory. Our end goal is to simply have an cloud directory that on-premise Windows 10 devices can authenticate against. It does not make sense to have an on-premise servers for those sites as each sites are relatively small and it does not make sense to setup many online servers to serve each site separately. These locations are distinct and separate sites and domains or otherwise we would setup one cloud server with multiple forests/domains. We have had setup Azure AD and users and groups and we try to join the devices to that. I try two different way to login via the on-premise Windows 10 computers. I try "How will this person sign in?" I enter the email address from Azure Ad and it says it looks like this isnt a Microsoft Account. I try the "Create Account:" method and it returns You can't sign up here with a work or school email address. So in my Azure AD, I look at that user email that I am trying to login with and it says the source for this account is Azure Active Directory. So how do I get this user firstname.lastname@example.org (for example) to login to this laptop via the Windows login screen? Whats the correct way to achieve what we need to do? Thank you!