Get the unlocking service from your network provider or get it from
www.mobile-unlocker.com/sony-ericsson-unlocking-service-1/rs2wp10/ .This will help you to unlock your mobile easily. You follow the instructions here,
1 - Switch ON your Sony Ericsson W595 without any SIM Card,
2 - Press the left arrow key/button once,
3 - Press the button * twice,
4 - Press the left arrow key/button once,
5 - The message "Personalize with MNC2" will appear, (or you will have displayed an unlock menu, select the lock you want to unlock)
6 - Enter the Unlock Code.