Take a look at the RadarBox Help file Help > Contents or press the F1 key.
Look at Getting Started > Installation for instructions.
The RadarBox drivers are in the /Drivers folder as shown in this picture of the directory structure on the RadarBox Utilities website.
http://radarbox.gofreeserve.com/html/downloads.htmlIf at any stage, the install window says that it can't find a file, take note of which file it is then browse to where that file is - usually in /Drivers or Drivers/i386. If you can't find the file, use Windows search to locate it.
Another way of doing this is to watch the Device Manager > USB controllers ans see which 'device' disappears and reappears as you unplug and plug in RadarBox. You can then right click on it and go to the Drivers tab and click 'Update Driver' and go from there.
Once you can see AirNav RadarBox in the Device manager, you are in Business :-)
Remember to always use the same USB port, otherwise you will have to install the drivers for the new port too.