Cannot send e-mails from Outlook 2003 but can receive them

[Guest]

I have an AOL account and use Outlook 2003. It has been working fine for a
while but now I cannot send or reply to emails. I can receive them with no
problem. Here is the message I get back:

Your message did not reach some or all of the intended recipients.

Subject: RE: Now!
Sent: 2/28/2007 10:30 AM

The following recipient(s) could not be reached:

'(e-mail address removed)' on 2/28/2007 10:30 AM
554 TRANSACTION FAILED

I need some assistance to correct this issue.

 

[Guest]

NDR message 5.5.4 is usually an invalid address. Is "aim.com" part of your
actual email address?

 

[Guest]

Yes it is. I can send and receive emails from (e-mail address removed) just
fine. I do not use Outlook with that address. My other address is
(e-mail address removed). That is the one that I use Outlook with. It is an AOL
account. I can recieve emails there but cannot send. When I send I get the
"554 TRANSACTION FAILED" response.