Mar 21 2019 05:15 AM
So, I have a weird situation. I have a customer that starts all their admin accounts with $ in the username and UPN. We've noticed that when we sync these accounts to O365, the $ is changed to _, which is odd because most of the time when there's an invalid character in the UPN you get an error in Synchronization Service.
My question is - Is this expected behavior, changing the $ to _? Personally, my recommendation is to remove the $ from the UPN and keep it for the domain\username, but considering the customer I would like to have more information first.
Mar 21 2019 05:47 AM
This is by design, see article
Even through dollar ($) is not explicitly on this list the list itself is not exhaustive and can be expected to extend to other special characters such as Pound (£) Hash (#) and Brackets ([]). I myself have experienced this with Dollar, Hash and Ampersand.
I would recommend what you said - remove these types of special characters completely and change them to something supported like ADM_username
Hope that answers your question
Best, Chris