When trying to update my maps using the download from the Map and Services section of the Route Planner web page, the update failed and I lost the maps completely. I called my dealer and booked the car in for them to try and fix the problem. As I had a week to wait I thought I would try and find the problem.
I searched through several forums and found the following:
I had to use a 64GB USB stick as a 32GB did not have enough space.
It must be a USB 3 stick and formatted to FAT32. Mine was originally formatted to exFAT. Windows 10 does not give the option to format FAT32.
Luckily I have a utility program that allows it. It can also be done using an administrator command prompt. Google will find the command to use.
The USB stick must be connected to a USB3 port on the computer. I tried three times with the stick in a USB 2 port before I found this tip in a forum.
The download from Maps and Services on the Route Planner website takes ages. about 7 hours on my PC.
I disabled eco stop/start in the car during the update.
The update took about 15 minutes.
I am now happily up and running.
Hope this helps anyone else having problems.