Thanks for the reply. No as said I only use Basecamp. I'm pretty nieve about this type of thing I'm afraid.
As I also said it still seems to be working but I haven't tried a large route on Basecamp etc.
Has no one else had this message? Seems strange but maybe still OK.

Hi Guys.
Sorry if this has been covered before, I’m new to the Forum but cannot find anything on it.
I have a motorcycle mounted Zumo-595. It's a few years old and has always been quite good. In the past year however I have an error message every time I turn it on saying “Maps are corrupt and cannot ...