Don't bad mouth the mother. Thats all she knows. Beings she is 27 now she may be mature enough to sit down and talk to you. I would just start out by saying you are her father and want her in your life if she is willing to take the time to get to know you. Don't push. Don't be angry. You may never know why the mom did what she did but you have to understand that putting things in kids heads can be damaging to the heart and mind and if thats all she has heard for years about you, she will have to see for  herself what kind of person you are...