Outgoing mail from Outlook.com sticks in Drafts folder


Outlook version
Outlook 2013 64 bit
Email Account
When sending mail from Outlook.com (OWA) it immediately goes to the Drafts folder and stays there. There is no error message. Then trying to send it from the Drafts folder generates "Error: The message can't be sent right now. Please try again later."
This happens with all connected accounts and is independent of the browser (Chrome, IE) used to access OWA. Incoming mail works OK. Desktop Outlook with the same email settings works OK.
This appears to be a known problem, but not much response/suggestions.