In the section where I can manage my private messages, I see three 'folders': Inbox, Outbox, Sent Messages.
What is the difference between the latter two?
When I compare it with my email system, the Outbox option could indicate that the messages are not sent yet.
Is this correct?
It might explain why I didn't get a reaction

If the messages in the Outbox are indeed not sent yet, how can I then do send them?