I get this when I send a email from the outside to a group that I have created in exchange a month or so ago. I am logged into it now and have been looking around but I dont see what I am looking for. I also cant seem to view any log files via message logs :(
Remote host said: 550 cuda_nsu 5.1.1 User unknown [RCPT_TO]
and the rcpt_to is the group I created in AD.
I am also not sure if there is a LDAP sync or not, I have not found that either.