Unable to send to external clients using exchange 2010

We have recently migrated to server 08 and exchange 2010 from sbs 2003.  We are able to send internally, but not externally.  We have created an internet send connector, with smart host (tried with direct dns also).  The error we receive is :

Delivery has failed to these recipients or groups:

external@yahoo.co.nz (external@yahoo.co.nz)
Your message wasn't delivered due to a permission or security issue. It may have been rejected by a moderator, the address may only accept e-mail from certain senders, or another restriction may be preventing delivery.

The following organization rejected your message: exchange.ourdomain.local.

Diagnostic information for administrators:

Generating server: exchange.ourdomain.local

exchange.ourdomain.local#530 5.7.1 Client was not authenticated ##

Can EE please help.  We have been hitting it hard to try and resolve (EE that is, not the bottle)..

Thank you.

Who is Participating?
Shreedhar EtteConnect With a Mentor Commented:

Go to your send connector and change the FQDN name.

FQDN has do be external domain name.

Also refer these:


Hope this helps,

richard2genAuthor Commented:
Good peeps, it appears my brain hath farted... I created an "internal" send connector, thinking I would need that for internal mail routing aswell.  That was stopping mail from goin out.

Thank you anyways.
Dont forget to test it


Test for Inbound and outbound SMTP
Use IE for tests.

richard2genAuthor Commented:
Good sirs, I thank thee...  The external FQDN helped get me over the line...
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