e-mail messages wont send, why?

Really appreciate all the advice but still stuck - change the setting....but looked for a password & the only password I've ever used for e-mail isn't working. Will call NTL & see if I can sort it out. Probably would be easier to change address !!
For sending e-mail on standard SMTP servers (which is what most ISPs use), you usually don't need a password. Disable any password or authentication options related to SMTP or sending mail.

You do need a password for retrieving e-mail.
 
Thanks guys for the help, the above remedy seem's to have sorted the problem,took a while to get it right but back working now.
 
Thanks to all, Technolgists advice :
Server settings E-Mail Server
POP3: pop.upcmail.ie
SMTP: smtp.upcmail.ie
+ UN-ticking the "my computer needs suthorisation" worked
 
Hoping someone can help me with a related few queries:-

Got a new iPhone 4 with eMobile and am trying to set up e-mail. When I'm in the office, my incoming mail server setting is mail.mariannesurl.com (substituting mariannesurl.com for my actual address) and my outgoing mail server is mail1.eircom.net but this only works when I'm connected through my Eircom broadband router.

Anyone know what the outgoing mail server settings for eMobile are? I can't find them on the eMobile website.

Similarly, I have a pay-as-you-go wireless internet Vodafone dongle for use on the laptop when out and about. Anyone know what the outgoing mail server settings for that are, if I want to send e-mail using it?

Finally, I'm going abroad shortly and plan to use both iPhone and Vodafone dongle. Do I need to change the outgoing mail settings when roaming?

Thanks in advance.