Hello there, I have a co-ordinates (hopefully non) problem... In Arc the map is using OS data as a basemap, but when I bring in other layers from OS, Arc is saying that the co-ordinates don't match - but they do?!! Also, I have a feeling that the 10m grid ref is actually 1m grid ref... So, what has happened and how do I fix it? Or shall I just change each 10 meter grid to 1 metre grid?