Thanks for your prompt response catymag, i couldn't work out how to tell if the map was locked or unlocked with Gmaptool???? On the info page it just listed all of the many hundreds of individual maps contained in the composite + FID no's and the like.

So i reformatted, and then ran Fast Imamge unlocked 2.1 and reloaded it onto the sd.

Basecamp sees it no probs and reads it etc, so I'd assume this means its truly unlocked, but the 3760 still does not??

Its driving me nuts?!

Next step please.