In Windows 10, someone decided to change the name of the System Tray.  It is now called the Notification Area.

Here is how to show all Icons in the Windows Notification Area. (Well, it’s one way to get there.)

1. Right-click a free spot on the Taskbar and left-click select Properties.  The Taskbar and Start Menu Properties will appear.
2. Next to the words “Notification Area:” Click the Customize Button. Edge will open and the left menu will automatically highlight Notifications and Actions. 
   
3. Select the Link on the right that says “Select which icons appear on the taskbar.”  Why they call it the Taskbar at this point is a misnomer, or rather misleading. But this will take you to the appropriate “Settings” screen for Taskbar / or  / Notification Area Icons.
4. Select or Turn “ON” or “OFF” beneath the phrase “Always show all icons in the Notification Area.”
5. X-out of Edge.