As HiView 3.0 supports more functions than version 2.0, the config files are not compatible. However there's a workaround:

You can open the hvw-file saved by HiView 2.0 in a text editor and copy everything between "<Devices>" and "</Devices> into a blank HiView 3.0 configuration file saved before. (replacing any present <Devices> section)
This file should be loadable by HiView 3.0 containing all devices saved in the HiView 2.0 configuration file.