I recently installed Ubuntu and set up Evolution E-Mail. Although I can receive incoming email perfectly, I can't send any messages. These just go to the Evolution Outbox and stay there.
I am using several E-Mail addresses: Hotmail, Gmail, Yahoo and Sky. Gmail and Sky now work, (i.e., E-Mail can be received AND sent) but hotmail (my primary E-Mail address) and Yahoo will only receive.
What could I have misconfigured when setting the system up?