It's quite easy to click the Delay Delivery button accidentally when you had intended to use one of the buttons either side. In Outlook 2013, under the Options tab (when composing an email), there is a group of three buttons: Save Sent Item To, Delay Delivery and Direct Replies To: Accidental use of 'delay delivery' option If outgoing email is being stored in your Outbox folder, there are two known possible causes: use of the delivery delay option, or a damaged Outlook profile. This article applies only to staff and researchers, on the Exchange mail system as used with Outlook.
2565Email from Outlook is being delayed by getting stuck in the 'Outbox'.