Dell D505 bluescreeninng when it is un-docked.

Hi can anyone help?

Our D505 laptops are used with a docking station.
Everytime you un-dock it a few seconds later it blue
screens. I have tried updating the drivers but it does not
seem to make a difference.

The laptop runs perfectly when it is running on the dock
or when it is used off of it from the start.

Any help would be appriciated.

Thanks