From what I learned here in just a couple of days, you need first to know the software you have. Then you update the operating system, then find a recent map to replace the cd/dvd on the unit. To do that (update OS), check the software you have. Push the menu button and scroll to "SET". Push the knob and on one of the corners it should be something like 3-2/50 or 2-1/60. From what I learned here, the 3- means you have a MK3 hardware nav system. The other numbers are the software.

I'm still looking for a recent map for my brothers 2002-E46 320d touring.

Good luck and shout for help, people here will do so.