Safely Remove Icon In Taskbar Missing

First reboot the PC in most cases the icon re-appears

Go Start then type Cmd, copy and paste (rundll32.exe shell32.dll,Control_RunDLL hotplug.dll)

Confirm Display Device Components is ticked.

Confirm the icon is enabled on the taskbar : Go to Control Panel\All Control Panel Items\Notification Area Icons.

Another way to confirm is  Start, type regedit, run it, UAC click ok, make your way to
: HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer

Enable Auto Tray value should be 0 for enable and 1 for disable

Also try clearing notification cache : run ccleaner confirm that under the windows tab / Advanced Tray Notification Cache is ticked.

Last resort right click on the desktop, new text document, name it clearnotificationicon.bat, then double click on it and paste this in it.

taskkill /im explorer.exe /freg delete "HKCU\Software\Classes\Local Settings\Software\Microsoft\Windows\CurrentVersion\TrayNotify" /v IconStreams /freg delete "HKCU\Software\Classes\Local Settings\Software\Microsoft\Windows\CurrentVersion\TrayNotify" /v PastIconsStream /fstart "Shell Restarter" /d "%systemroot%" /i /normal explorer.exe

File save, exit, then run the bat file