In Windows 7 / 8, if System icons were not showing in Taskbar, you could set them through the Notification Area Icons Contraol Panel applet. But things appear to have changed in Windows 10.

Now Right-click Taskbar > Properties. Under Taskbar tab click on Notification area Customize. The following window will open. The only options you see here under Settings > System > Notifications & actions > Show notifications from these apps are for:

  1. Optional Features
  2. Outlook
  3. Windows Feedback.

You will not see a Notification Area Icons Control Panel applet, which allowed you to select which icons and notifiations appear on the taskbar.