Features on portable do not work after docking or undocking due to Plug & Play.

Cause:

The computer does not have a plug-and-play BIOS. A plug-and-play BIOS is required to support hot or warm docking and undocking.

Solution:

Turn the computer off before docking or undocking. Contact the computer manufacturer to upgrade to a plug-and-play BIOS.
NOTE: Some computer manufacturers will not supply a plug-and-play BIOS for certain computer models.