TAfter a couple more attempts copying the files it seems to have worked - no GPS attached, no memory stick attached, so it must be working off the virtual memory. So after perhaps half a dozen attempts and a few PC reboots, I have got there. Obviously I have no idea why it took so long, and so many attempts, but this is now working OK. Hopefully it will work considerably more smoothly when I get around to buying additional maps. Thanks again.