Ford c max Key fob won't reprogram. Help me!!!?

Hi, can someone please please help me? I've got a 2005 Focus and the battery was getting low on the key fob so I replaced the battery. The key didin't work at all so I followed your steps to reset it and I'm getting both the first beep (after 4 turns) and the second (when I press a button) but the key still won't work. It's driving me mad!! I've tried waiting for 10 seconds to laps before trying the doors and I've tried turning the key to position 2 but still no joy. I can hear a noise under the bonnet when I'm pressing the buttons. I would be realy gratefull for any help on this. Thanks