The problem:
Outlook 2013 will not send email with a particular symbol, namely a piece of paper with a pencil.
Such a symbol is probably created when I edit an email. The top symbol with the traditional envelope, sends no trouble, the bottom one sticks in the Outbox and is not sent.
Question: What causes this behaviour? How can I overcome it and send my email.
Best Answer
That icon represents a draft in the outbox, or something edited while it was in the outbox. Try disabling add-ins like iCloud. source