Outlook 2003 send & recieve

i am a newbie to using forums but i am getting zero help from my isp virgin media, i am able to recieve mail but unable to send mail, if i use my webmail i can send and recieve, virgin media are blaming outlook but i believe that it is their server as i have learnt that they are using some methods to block spam and this could be the cause of my inability to send mail.

This is the error message that i recieve:

Task 'Home - Sending' reported error (0x800CCC67) : ' The server responded: 421 aamtaout04-winn.ispmail.ntl.com connection refused from [86.27.211.218]'

Hope that someone can help

If any person has recieved the following error msg whilst using virgin.net here is the fix that works.
421 aamtaout01-winn.ispmail.ntl.com connection refused from [86.27.211.218]
This has happened to me about a week ago and i have heard that there are people out there who have been unable to send for over a month and virgin keep blaming Outlook.
i use ntlworld.com
all that i have changed is the smtp settings from pop.ntlworld.com to pop.virgin.net and my emails are once again operating.
amazing that all of these virgin.net techs couldn't work that one out for themselves.
Please pass this info around as there are lots of frustrated people out there, as i was.
Cheers
bigboy