I was trying to find a way of removing the Safely Remove Hardware icon in the taskbar and after scratting around trying to find ways of enabling the Customize Notifications message (which was greyed out) by right-clicking in the taskbar I found a simpler way of doing it.

Right-Click on the Start Button. On the Taskbar tab next to Hide Inactive Icons (make sure this is checked) click Customize – this brings up the Customize Notifications dialog box. Find the entry that says Safely Remove Hardware and change it to Always Hide. Click OK then OK again and the icon has gone.

This isn’t the ideal solution as all it really does his hide the icon and if the user clicks on the unhide button (backward arrow) then the icon reappears. But like most things, it’ll do for now.