Exchange 2010 the distribution group setting "require all senders are authenticated" is not working

Powershell shows "RequireSenderAuthenticationEnabled     : True" and I do not have "Externally secured" checked on any receive connectors, but I can still send to this group from the outside. I tried deleting and recreating the group, but it still accepts messages. Email comes in from a local Spam server. Any Ideas?
AntExpertIT ManagerAsked:
Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Will SzymkowskiSenior Solution ArchitectCommented:
If you send from a legitimate email to this group does it work? Sometimes spammers still find a way to mask the domain which allows the email to pass through. If this is strictly a spamming this you might want to take a look at your spam filter to see if there are any other logic rules you can put in place.

However, you are always going to get some sort of spam even with the best spam appliances out there.

AntExpertIT ManagerAuthor Commented:
I can send from a generic gmail account to this group yes, or any group for that matter, since the "require all senders are authenticated" does not work.
Will SzymkowskiSenior Solution ArchitectCommented:
Does this happen for any group that are you using with "Require Authenticaiton Enabled True"? or just this specific group.

If this affects all groups then i would look at our Receive Connectors and make sure that the proper permission groups and authentication on the default receive connector and also any custom ones you might have as well.

If all groups are acting this way then something has changed at the org/recevie connector level.

Determine the Perfect Price for Your IT Services

Do you wonder if your IT business is truly profitable or if you should raise your prices? Learn how to calculate your overhead burden with our free interactive tool and use it to determine the right price for your IT services. Download your free eBook now!

AntExpertIT ManagerAuthor Commented:
Yes all groups seem to ignore this setting and I can't identify whats wrong with the receive connectors? Email is delivered from a local spam server, could that have something to do with it?
Will SzymkowskiSenior Solution ArchitectCommented:
It is possible. Not sure why all groups would have this setting ignored. Have you tried to check the permissions on your default receive connectors? Also have you tried to re-create them?

AntExpertIT ManagerAuthor Commented:
I just connected to the Exchange server via telnet, and it does reject messages to the group and indicates that authentication is required, so based on that, it appears the server is doing what it should. It must have something to do with how the spam server is forwarding messages to Exchange. If you have any ideas on how this should be configured,  I would appreciate your input.
AntExpertIT ManagerAuthor Commented:
Found the Solution. We are using Symantec Brightmail Gateway for email Spam filtering. There is a setting on the server under "address resolution options"  called "enable distribution list expansion" that was checked. I unchecked this option and everything is working as it should.

Thanks Will for helping.

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
AntExpertIT ManagerAuthor Commented:
I discovered that the exchange server was not the problem by using telnet.
I then began to research my Spam server and discovered the fix to the problem.
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today

From novice to tech pro — start learning today.