I have made pasword protected my Samsung GT-E2152. But unfortunatly I forgot my password. I have tried a lot of PW but useless. Can any body help me. How I can open my password ?

Your phone will be unusable if you cannot remember the seciruty pass code no matter how hard you try or regardless if you replce the SIM card. Ehat you should do is to take your phone to any nearest cel shops who specialize in cracking codes or resetting phones, they just have to connect your phone to their computer and do stuff to decode or reset your phone.