In MM02, whenever we give invalid change number in the inital screen, i need to display a window(enhancement)before the error messge(change no does not exist) which should give list of change numbers for that material. For that, i need to find a BADI. I tried ECM_EXIT, But it works only for valid change numbers. And i need to find the <b>table which has material numbers and change numbers</b>. its very urgent. please help me out of this.