Quote Originally Posted by reichstall View Post
no y don't understand my maps are unlocked legally on my computer but when I transfer them to my unit they become locked
If they are legally unlocked on the PC for your SP 2820 then the necessary *.unl code will be generated when you transfer the maps to your device using MapInstall. So, a couple of questions: Did you buy the PC installed mapping data (i) for the 2820 or (ii) for another device?

If you bought them for the 2820 then contact Garmin about the problem. If you bought them for another device then they will only be available unlocked exclusively to that other device.