If the eject icon is enabled in the system tray settings but does not appear, it may be due to a policy setting that hides notification area icons. You can check the policy setting under User Configuration > Administrative Templates > Start Menu and Taskbar > Hide the notification area. If this policy is enabled, it could prevent the eject icon from being displayed.
Additionally, ensure that the device you are trying to eject is indeed recognized as an ejectable device by the system. If the device is not properly recognized, the eject icon may not appear.
If you continue to experience issues, consider restarting your computer or checking for any updates that might affect system tray functionality.