Try PINGing the device from the PC that you are trying to view the webscreen from.
If the PING is not successful, check the physical connection, then confirm that the Ethernet parameters are set correctly on the HMC screen. You can do this by holding the lower left corner of the screen while the device is powering on.
If the Ethernet parameters are not correct, then you can download the correct Ethernet parameters from MAPware 7000 over USB. To set the correct parameters, go to Project > Properties > Ethernet. Click OK and open the download manager. Select “Ethernet Settings” and download.