Hi

My battery went dead and since then the navigation either displays 'please wait' or please insert CD/DVD.

I have read I may need to re install or update the firmware but cannot find exactly how to do it.

Also do I have to re install the same version firmware or update to a newer version?

Any help would be greatly appreciated.

The car is an E46 M3 2003 facelift.

I look forward to some advice.

Many thanks.