Is this a normal email account? Is the mention of new accounts normal to you?
If this is a normal email account, I assume you're using Outlook or Outlook Express. Go to Tools, Email Accounts, View or change existing email accounts. Select the account and choose Advanced. Check that the broadband conenction is selected as the connection used.
Also disable scanning of outgoing email in any antivirus software.
I'm groping really, but this might help.