I am trying to set up Edge sync for domain joined users. They authenticate on our terminal server using the Domain\Username format. The sign in works in edge, but the synchronisation refuses. Whenever i use the username@domain.com format it will both sign and and synchronise.
I assume this has something to do with the way Azure only recognising the UPN format.
Is there any way to either make Edge log users in using the UPN format or Azure recognizing/map the domain\username accounts?