The Orange SPV C600 can be unlocked by contacting the cell phone service provider through the helpline service or by visiting the center of the service provider. The other way to unlock the phone is to use the remote unlocking method which is available on the internet. In order to unlock this way, you must have an unlocking software (provided by the website) and the USB cable (provided with the phone when you bought it). This procedure requires you to pay some amount of fee.
The instructions and other information on how to unlock your Orange SPV C600 is provided in the following link: