I have a problem with Message delivery restrictions. I have Exchange 2010 SP1 with Rollup Update 5. I have checked “require that all senders are authorized” in one distribution group, but everybody from outside of our organization are still able send to this group. Why?
Hi there,
I recommend you check on the receive connector on the Authentication tab if externally secured option is ticked.
If the problem still persist them you should then create a new Universal distribution group and check require that all senders are authenticated and send mail from an external provider (gmail,yahoo or Hotmail) and can still receive the mail
In ADSEDIT
msExchRequireAuthToSendTo = True.
Be sure to check the Internet Receive connector after everything has been done.
This is normally known as message throttling.
I hope the given solution helps you solve your problem, since the Microsoft Exchange 2010 is needs various updates to properly function.
