Hope you didnt steal it!
here is how u can reset it
1) Flashing in town , that would cost you around 5 to ten bucks.
2) have the fone technicians in town remove the security code for you.
3) do an extensive research on how to remove secutiy code on google, you have to use navifirm and so on, just google it, there are comprehensive tutorials and you can DIY.
4)You can hard reset your c3 by first switiching it off, then press *+3+call button(the green one) all at once without letting go and then power it up. U might need someone to help you
option 1 and 4 you will lose all user data, apps and settings