But this will also bounce back the emails which are sent through some applications which do not require authentication. We have some applications that are sending emails to Distribution list without authentication check.
exchangelist-bounce@xxxxxxxxxxxxx [mailto:exchangelist-bounce@xxxxxxxxxxxxx] On Behalf Of James Chong
Use set-distributiongroup with the requiresenderauthenticationenabled switch
I have Exchange 2007 in my organization. We have lots of distribution lists. On one of specific distribution list, I want that only internal users should send emails. If external user send email it should bounce back. Please let me know how can I achieve this.