Error 554 5.7.1 Error: deny openrelay

In Exchange 2010 we have our main domain name and then we have two other domain names, so each user they have 3 possible email addresses they can use.  We can receive from all three addresses internally.  However we can only receive from external email addresses to the main email address.  If I try to send an email address from like gmail I get the following error:  554 5.7.1 Error: deny openrelay.  Where would I need to add these other email addresses in Exchange?
PDISAsked:
Who is Participating?

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

x
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.

Vaseem MohammedCommented:
Check this article.
https://technet.microsoft.com/en-us/library/bb124911%28v=exchg.141%29.aspx
Also make sure you have completed the per-requisites mentioned in above article i.e., MX records in place for the additional domains.
Simon Butler (Sembee)ConsultantCommented:
I am pretty sure that is NOT an Exchange error.
Therefore you should check that the other domains have their MX records pointing at your server and not somewhere else.

Simon.

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
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
Exchange

From novice to tech pro — start learning today.