After I had to delete and recreate a user account in Exchange 2007, I am getting a non-delivery error, on internally sent emails to this newly created user. This is happening for all users who try to send emails to this one user.
Also I'm able to send email to this new user if I reply to his email.
This is how error looks like:
IMCEAEX-_O=EXCHANGENAME_OU=EXCHANGE+20ADMINISTRATIVE+20GROUP+20+28NFDVBOHF22RRTLT+29_CN=RECIPIENTS_CN=User19ax23be6@domainname.com
#550 5.1.1 RESOLVER.ADR.ExRecipNotFound; not found ##