If you have installed the files on a memory card, it must be recognized as an extension of the GPS memory.Once it is recognized it is renamed NAVIGONSD. I had the same problem as you, before attempting a reset make a backup of the gps memory.
Once the sd card is renamed NavigonSD, it's simple :
I complete my explanation of the previous page !
1. Open the folder NavigonSD.
2. Create a folder Navigon in NavigonSD.
3. in this folder Navigon create a folder Map and another POI.
4. Open the folder Map and put all the cards you want and all NFS files undermentioned :
France.map and another countries
For POI open the folder POI and put in the folder undermentioned :
I also added all the .pom language files from the memory of my GPS in the folder.
5. Once all the items have been copied, close Navigon SD disconnect your gps from the computer
6. Go to configuration, click on map representation, go to page 2 and click on Country and select Q3 2016.
7.The gps will restart automatically and it's good.
Good evening holyhead,
Concerning radars it works, it detects fixed radars, it warns when entering an area where there is a radar and approaching the radar by a red zone on the screen.