One the things that really irritates me about Outlook is that when you click reply it doesn’t close the original message. Here’s how to change that.
Make Outlook 2013 Close the Original Message When You Reply To a Mail
The first thing you need to do is click on File to enter backstage view.
Then click on Options.
When the Outlook Options dialog opens, switch over to mail on the left hand side.
Finally, scroll down until you see a check box labeled “Close original message window when replying or forwarding”. Make sure that you tick this box, its super important and will greatly enhance you Outlook experience
That’s all there is to it.