undeliverable e-mail 5.1.0 error SBS 2003

Local AD is intexpr.local
External is www.intexpr.com

All users seem to be affected by this.  They cannot send to a couple of different domains.

Thx

Shawn

I see, its external domains you cant send to? In that case in your DNS server I would change your DNS forwarders temporarily to opendns's DNS servers which are 208.67.222.222 and 208.67.220.220.

This will prove/disprove the DNS theory.

Changed ny DNS settings but I am still receiving this error message

 The e-mail system was unable to deliver the message, but did not report a specific reason.  Check the address and try again.  If it still fails, contact your system administrator.
            < isp.att.net #5.0.0 smtp; (Permanent Failure: Other undefined Status)>

Any other ideas????

Where did you change them? the SMTP virtual server also has an option for overriding the Servers DNS settings? Have a check in there. TBH it has to be sopme kind of dns error?

If you run NSLookup on the server and type

set type=mx

Then enter the domain names of the failing addresses, does it resolve, and more importantly does it resolve correctly?

I changed the DNS settings on the forwarders in the DNS Manager.  I see a place in the SMTP virtual server on the advanced delivery tab that has a spot for smarthost.  There is nothing in there.  Do I need to plug in my smarthost IP here also?

Here are the results of my nslookup....everything looks fine.....

Default Server:  server.internationalexpress.local
Address:  192.168.1.5

> set type=mx
> ccsofc.com
Server:  server.internationalexpress.local
Address:  192.168.1.5

Non-authoritative answer:
ccsofc.com      MX preference = 0, mail exchanger = smtp.secureserver.net
ccsofc.com      MX preference = 10, mail exchanger = mailstore1.secureserver.net

> nssolutions.biz
Server:  server.internationalexpress.local
Address:  192.168.1.5

Non-authoritative answer:
nssolutions.biz MX preference = 0, mail exchanger = smtp.secureserver.net
nssolutions.biz MX preference = 10, mail exchanger = mailstore1.secureserver.net

Any other ideas??????????

More information:  This is really strange....If I send an email to the ccsofc.com or any of the domains in question and "request a delivery receipt" in Outlook the email goes through and does not get kicked back!

What is going on?  Wanted to also let you know that I am running Symantec Mail Information for Exchange.  Not sure if this has anything to do with it, but thought you should know.

Another update....I have one user that can send emails to the ccsofc.com domain if a delivery receipt is requested and I have a another user that cannot send email to this doamin.  The message gets kicked back to them from the system administrator with the same error message:

The e-mail address could not be found.  Perhaps the recipient moved to a different e-mail organization, or there was a mistake in the address.  Check the address and try again.
            < isp.att.net #5.1.0 smtp; (Permanent Failure: Other address status)>

Totally LOST!!!!!!!!!

One question.. why do both of those domains resolve to the same MX records.. are they the same company?

No...they are different companies hosted by GoDaddy.

are these the only 2 companies you cant send to?

If so its worth calling go daddy's support I would say?

NO...I cant send to other companies as well as these two....did you see my previous posts.  Why can one user send to them and another can't?  Makes no sense...I have got to get this figured out!

I did read them but chose to ignore them lol, your right doesnt make sense..

I have to say when something makes not sense at all for me I start to suspect virus's, can you do a safe mode scan on some of the suspect machines to be sure?

.. Im in scotland by the way so I'll be in bed soon.. dont know where you are though..

Actually I just scanned all of the computers on the network 2 days ago with Windows One Care and it found a couple of virus' but I was able to remove them.  Scanned all computers again and they came up clean.  I am at a loss right now!

I am in South Carolina, US

Right, I'll have a think about this one in work today and get back to you.

Any help out there....i am ready to throw this exchange server out the door.

Ok ...i think i have narrowed down the problem.  I have two Outlook 2007 clients and the rest are 2003 clients.  The two 2007 clients come up with a system undeliverbale message on the two domains in question.  The 2003 clients seem to be fine.

Any ideas????

Downgrade them to 2003 to verify that its a SW problem..

Update...
I unistalled Office 2007 Basic last night on the two workstations in questions.  I re-installed Office 2003 Professional.  The two workstations that could not send email to the two domains in question can now send email to them with no problems.  What is the difference between 2003 to 2007?  Are there some security features in 2007 that need to be turned off?  Right now everything is working, but my client now has two copies of Office 2007 that they cannot use because of the Outlook 2007 email problem.

Thx

Shawn

DAMN DAMN DAMN......
Back to square one again!  After down grading the two users' workstations to 2003 they cannot send email to the two domains in question again!  Same error as before:  It worked for one day!

The e-mail address could not be found.  Perhaps the recipient moved to a different e-mail organization, or there was a mistake in the address.  Check the address and try again.

Other users on the Network can send mail to the domains in question with no problems.  I am at my breaking point!  What is going on?

PLEASE HELP!!!!

By the way I have a Smarthost setup on the exchange server with AT&T.

ANYBODY OUT THERE??????

fixed