Hi, I have changed service provider 3 days ago. They sent me a self-installing modem etc, and I set the parameters for email accounts as they said. Changed the Port number to 587 and the outgoing mail server to SMTP.fastwebnet.it as it says on their website.

However, while I manage to download mail, I am still unable to send out any mail. I have 3 email accounts for work reasons, and this is a huge obstacle to getting my work done! What can be going wrong?

Pasted below are the errore messages I receive.

Many thanks for any help you can give.

The message could not be sent because the server rejected the sender's email address. The sender's email address was *** Email address is removed for privacy ***'.
Subject 'Testa alice'
Server Error: 530
Server Response: 530 authentication required for mail submission
Server: 'SMTP.fastwebnet.it'
Windows Live Mail Error ID: 0x800CCC78
Protocol: SMTP
Port: 587
Secure(SSL): No

The message could not be sent because the server rejected the sender's email address. The sender's email address was '*** Email address is removed for privacy ***'.
Subject 'Test'
Server Error: 530
Server Response: 530 authentication required for mail submission
Server: 'SMTP.fastwebnet.it'
Windows Live Mail Error ID: 0x800CCC78
Protocol: SMTP
Port: 587
Secure(SSL): No