Are you trying to use pop or imap?
My imap settings are:
Your Neme: "Yours Truly"
email address "Yourstrulyaddy@ntlworld.com"
Incoming mail server: imap.ntlworld.com
outgoing mail server (SMTP): smtp.ntlworld.com
Logon info: email@example.com
remember password: check
Require logon using Secure Password Authentication: not checked
obviously the yourstrulyaddy isn't real
and the password is the one for that email account.
If I recall correctly I had to select the imap option in the vm email account website settings. I know there are also issues if you are not on a VM IP when you try to send mail via the vm servers.