If the following message is continuously displayed when viewing a Fisheye camera on the iVMS-4200:
Apart from downloading and installing the plug-in in the message, you can also try installing the executable found in the zipped file to repair the DirectX on the PC:
Once the Direcct X is installed, restart it and try it again. In case it does not work, it must be some failure or you do not have permissions to install them in this PC, for what you will have to consult with the system administrator