My Apple mobile device cannot send mail

Before leveraging the vast resources available from Apple to it’s minions (https://support.apple.com/en-al/HT201320), make note of one helpful hint from TaosNet…

Although iOS displays the Outgoing Mail Server’s fields of Username and Password as Optional, in grey text, nearly every server worldwide requires those to be filled in. So, hunt and peck your complete email address for Username and your email password for Password.