I purchased the Garmin City Navigator NT North America software recently (happy birthday to me!), and was having a bit of trouble installing the "unlock" code that must be retrieved from Garmin's website.
The description on their site didn't seem to match the user interface on the latest version of the software, at first. I tried a couple of different things, but just couldn't seem to get the unlock code to work for me. Buyers are required to retrieve a one-time-use code from Garmin in order to use all of the features of the software (to prevent people from installing the maps on all of their buddies' GPS units).
I contacted Garmin's customer support through their website, and got a very polite, and very helpful response very quickly. Garmin walked me through the process of unlocking the software, and did it without much hooplah. What a refreshing change of pace!
I wish that all customer support venues were as helpful as Garmin's was (hello, Groundspeak?).