fatal application error?

hi i have a sony nuv-u70t i tried to load the new maps,on doing this i have come across a problem it goes like this.
get as far as the loading, it then pings saying fatal application error.
application nav-u.exe has performed an ilegal operation and will be shut down. if the problem persits, contact the program vendor.
program; nav-u.exe
exception; 0xC0000005
adress; 0006ED94
does anyone know of this problem,
thanks dave.

dave todd
August 2008