Strange Green Colour

[Nick]

Excel is throwing up a strange problem. When I create a
chart using the control key to select fields (they are not
consecutive) the background of all sheets in the file
turns a light green colour.

This is not a setting from the background colour of the
cells which still registers as No Fill. It doesn't really
present any problems until I use a piece of code to copy
the data to word. Then the macro crashes and cant recover.

Does anyone have any ideas what is causing this?

Thanks in advance.

Nick