None of your email accounts could send to this recipient + exchang

[LithiumKid1976]

hi,
I have a user here who is trying unsucessfully to send an email to a list of
users on a distribution list.

the Distribution list is made up of members that are not in our domain.
i have upgraded her version of outlook from office 2003 sp1 to office 2003
sp3.
Hermail account is on our exchange server.

None of this seems to solve the users issue.
Any suggestions.

Damien

 

[K. Orland]

Is that the extent of the error message? There is nothing further and no
error numbers or NDR codes returned?

 

[LithiumKid1976]

Hi kathleen,
Heres the return info that the user gets
-----------------------------------------------------------------------------------
Your message did not reach some or all of the intended recipients.

Subject: FW: Science@Sea: Closing friday 26th September 2008
Sent: 25/09/2008 14:25

The following recipient(s) could not be reached:

'A Ford' on 25/09/2008 14:25
The message could not be delivered because the recipient's
destination email system is unknown or invalid. Please check the address and
try again, or contact your system administrator to verify connectivity to the
email system of the recipient.
<Ourserver #5.1.2

 

[K. Orland]

This is an SMTP error, host unknown. An error is triggered when the host
name can’t be found. For example, when trying to send an email to jdoe@
nonexistantdomain.com.

 

[LithiumKid1976]

hi kathleen.

These are mails on a distribution list, and they are external e-mail
addresses, the users on it dont belong to our domain.
it returns that error i printed previously for all mails in that DL(30+),
even though they are valid email addresses.

does this change anything?
Thanks for your help thus far.
Damien

 

[N. Miller]

These are mails on a distribution list, and they are external e-mail
addresses, the users on it dont belong to our domain.
it returns that error i printed previously for all mails in that DL(30+),
even though they are valid email addresses.

does this change anything?
Thanks for your help thus far.

Probably means that the issue is with the configuration of Exchange, which
is beyond my expertise. I could help, possibly, if the MTA was Mercury/32.
But you would have to ask in an Exchange group.