Thanks for the reply Neil, and for the welcome. I've done lots of reading here... so I thank everyone for contributing.

It's been so long since I used the maps I have (with Mapsource on an old Intel Windows box I haven't turned on in years, but still hang on to, just in case I need something), I'd forgotten about the restriction on the lock codes -- for one particular unit only as you said, and of course, it's not for the GW's navi system. Which of course, explains my situation to a 'T.' Fortunately, I was able to find a way to unlock the maps here on this forum, so I'm ahead of the game now.

Thanks again for the memory lesson.

Ron