the above code appears occasionally when I have sent a message via Outlook
2003.
Do I need to alter settings etc?
In my outbox I have one message that has been there for days and will not
send. I have tried to delete it without success. Could the error code be
related to that problem?

For the first question, no. The 451 is being issued by the mail server and
needs to be resolved by whomever runs the server. Other than that, don't be
surprised if they ask you to turn on diagnostic logging in Outlook. This
log will help identify which server you are talking to since the company
could have multiple SMTP servers and it is just 1 out of the collection that
is acting funny.

For the second (stuck item in Outbox),
http://www.outlook-tips.net/howto/stuck_message.htm might be helpful. By
the way, you may have to run the Inbox repair tool (scanpst.exe) against
your .PST file to verify that there isn't any issues with it.

"David Alan" <David (E-Mail Removed)> wrote in message
news36F123D-AABF-4D5E-8EDE-(E-Mail Removed)...
> the above code appears occasionally when I have sent a message via Outlook
> 2003.
> Do I need to alter settings etc?
> In my outbox I have one message that has been there for days and will not
> send. I have tried to delete it without success. Could the error code be
> related to that problem?