Lock SIM card designed to preserve the security of such personal data, like phone book and messages stored in its memory. In addition, when the lock SIM card, you cannot use the personal numbers of the owners in case of loss or theft. The pin is a sequence of numbers, and if you don't change, then you will be able to use the one specified on a plastic box from SIM card.In the case if you changed it and forgot, you will need to use the Pak code designed to reset the password. You can also find it on the packaging from the SIM card. Otherwise, you will need to contact the support service of subscribers with whom you have contracted. It is necessary that the owner of the SIM card personally appeared with passport service Department of the operator and reiterated his desire to replace the SIM card. Personal data will be lost, but your number will be saved for you.You can also deal with password on the lock directly phone. In this case, blocked access to all the information contained on the mobile, and its use becomes impossible. For password recovery you will need to contact technical support of the manufacturer of your phone to request a code reset, and the resetting code of the firmware. The first code will cause all settings will be returned to the factory, the second in addition completely erase all of your personal files stored in the phone memory. Receive these codes directly from the manufacturer is necessary to ensure the safety of the operation. You can find the contacts of the manufacturer on the packaging from your phone or using the Internet and finding its official website using the brand and the name of your phone.