If I select the radio button in debug mode which populates the listview with data from the DS and then rung the "stepping into" it tries to add the row but comes up with the error. I'm guessing this means that there is data in the DS.
The reason I think this is becuase if i run the debug and do not click the 'radio button' to populate the listview and then run "stepping into" it jumps direct to my message box stating "there is nothing here".
Even though I have now re-written this thing from the ground up using Gridview instead of list view and made some great advances I'm still having the same problem with the bloody Save button and that infernal Dataset line!
Below is the new code: (I even added the connection the database AGAIN to try and make sure it got filled!)