thanks for your reply.
and on the device should I copy the navcore too?
I've just tested now and whan I open my device, I've the picture of the tomtom with squarred blue fond and just after I've an sd card who goes out the device & is crosed by a red.
I do something wrong but what I don't know.
Is my navcore who has a problem, I don't think because when I copy it on my device it's working.