Settings UPIN code—This code may be supplied with the USIM card.The USIM card is an enhanced version of the SIM card andis supported by UMTS mobile phones.PIN2 code—This code (4 to 8 digits) is supplied with some SIMcards, and is required to access some functions in your device.Lock code (also known as security code)—This code (5 digits)can be used to lock the device to avoid unauthorized use.The factory setting for the lock code is 12345. To avoidunauthorized use of your device, change the lock code. Keepthe new code secret and in a safe place separate from yourdevice. If you forget the code, contact your service provider.Personal unblocking key (PUK) code and PUK2 code—Thesecodes (8 digits) are required to change a blocked PIN codeor PIN2 code, respectively. If the codes are not suppliedwith the SIM card, contact the operator whose SIM card isin your device.Digital certificates should be used if you want to connect toan online bank or another site or remote server for actionsthat involve transferring confidential information. Theyshould also be used if you want to reduce the risk of virusesor other malicious software and be sure of the authenticityof software when downloading and installing software.Important: Even if the use of certificates makes therisks involved in remote connections and softwareinstallation considerably smaller, they must be usedcorrectly in order to benefit from increased security.The existence of a certificate does not offer anyprotection by itself; the certificate manager mustcontain correct, authentic, or trusted certificatesfor increased security to be available. Certificateshave a restricted lifetime. If "Expired certificate" or"Certificate not valid yet" is shown even if thecertificate should be valid, check that the current
