Outlook does not send messages when i click send and recieve

[Visine]

I have just switched to outlook from Oe 6 and having sorted the blocking of
Attachments have found that when I click send and receive Outlook checks all
accounts and receives and processes all mail rules but for some reason does
not send any mail in the outbox. The mail can be sent by clicking on it and
selecting send. When I shut down it says I have outgoing mail but still does
not send it.

Could some one tell me what setting I have missed please

Thanks

Baron