Exchange 2007 application log error Event ID 1035

I am seing the following error every 4 to 5 min appearing in the exchange 2007 application logs:
Event ID 1035
Inbound authentication failed with error LogonDenied for Receive connector Default 'Servername'. The authentication mechanism is Gssapi. The source IP address of the client who tried to authenticate to Microsoft Exchange is [

This is not an internal address... has anyone seen this before?
Should I be conserned about it?
Does anyone know the fix?

Thanks Much
Who is Participating?
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.


Do you have your mail being directly relayed from the Internet to your Hub transport server that is generating these errors?

Sounds like an authentication issue with your default recieve connector. You may want to check out this thread -

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
I dont see any solution posted there.  Can you give us more information on how to resolve this.  I am seeing the same error as above too.
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
Email Protocols

From novice to tech pro — start learning today.