I find the OneNote icon in the system tray very helpful for creating screen clipping and getting into one note quickly. If for some reason the icon “disappears” from the system tray, here’s how to get it back.
1. Open OneNote and head to Tools->Options.
2. In the Options dialogue box that appears, head down to the bottom of the left column and select Other.
3. Select the Place OneNote icon in the notification area of the taskbar and press ok.