How do I get rid of this email that is clogging up my "outbox" in Outlook?

There is an outgoing email that is "sending" from my Outlook outbox. It is somehow stalled. I have tried deleting it, nothing happens. I have tried to open it, but I get an error message saying that the email is already in the process of "sending", although it's been sending for 3 days. What to do?|||on the left side of page click empty beside mail and trash.|||disconnect internet then outlook, then select clear( on top left corner) you can clear trash mails, outbox etc with this.