Solved Show notifications from these apps

I went to "Turn notifications on or off". Then to PC settings. And it says "Show notifications from these apps".
It lists Calendar, games, mail, messaging, music, Outlook 2013, store and video. But the icon for Outlook 2013 is missing. How can I fix this?

This article may help to answer your question; however, I cannot verify its accuracy because I don't use Outlook 2013. Anyway here it is and good luck:
Outlook 2013 and Live Tile support in Windows 8 - Slipstick Systems

Somehow I got it fixed. I deleted Outlook from the taskbar. Then pinned it to the taskbar again. When I went back to settings the icon shows.

Way to go!