For some reason I cannot seem to create more than one body (extrude) from one sketch. I have ALWAYS done this previously but for some reason I can only choose a single area (or the whole sketch) for an extrude unless it has been extruded previously. I assume that a setting has changed but cannot work out what it could be? Any ideas?

For clarification it doesn't work only on new sketches. Any sketches from over 2 weeks ago are fine and can multi body?