If you are not seeing your laptop screen projected when you are docked or connected to the projector cable, your display settings may need to be changed. You can check this by right-clicking anywhere on your desktop, then select 'Display Settings'. Here, there should be a heading entitled 'Multiple Displays' with a drop-down box below it. Depending on what you want to have set, it should say 'Duplicate these displays' or 'Extend these displays'; if it says 'Show only on…' then you will want to change this to one of the other two settings. This setting seems to like to change when your laptop is powered on, removed, and then replaced onto your dock.