Hi devschool_mihaib, I want to help you with this question.
I think we talk about two different things. When you are in the assignment process on an Azure ARM scope you need to have the identities you want to assign a role to already in the tenant.
So it's not completely clear to me, how you invite a guest user at the same time you give the assignment to it.
Assignments on Azure ARM scopes won't send notifications via emails to the identity accounts.
But as you said, when you invite the guest user via EntraID initially, the guest user will get an invitation link on the guest user's mailbox
I hope this will solve the uncertainties
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