Error: "vDisk is not available. Please check your network PXE boot configuration and restart Imaging Wizard" or "Red X" on Provisioning Server

After installing the Target Device Software and rebooting the following symptoms can be seen: A Red X is displayed on top of the vDisk Status Applet in the Tray Bar After running the Imaging Wizard and rebooting the following message is shown:"vDisk is not available. Please check your network PXE...