contact from Contacts. To restrict calls by a countryprefix, enter the country prefix in the list of numbers.All phone numbers to which calls are allowed muststart with this country prefix.2. Select OptionsActivate fixed dialling. You needyour PIN2 code to activate and deactivate fixed diallingor edit your fixed dialling contacts. Contact your serviceprovider if you do not have the code. To cancel theservice, select OptionsDeactivate fixed dialling.Tip: To send text messages to the SIM contacts whilethe fixed dialling service is active, you need to addthe text message centre number to the fixed diallinglist.Certificate managerSelect MenuToolsSettingsGeneralSecurityCertificate management.Digital certificates are used to verify the origins ofsoftware but do not guarantee safety. There are fourdifferent types of certificates: authority certificates,personal certificates, trusted site certificates, and devicecertificates. During a secure connection, a server may senda server certificate to your device. Upon receipt, it ischecked through an authority certificate stored in yourdevice. You receive notification if the identity of the serveris not authentic or if you do not have the correct certificatein your device.You can download a certificate from a web site, or receivea certificate as a message. Certificates should be usedwhen you connect to an online bank or a remote server totransfer confidential information. They should also beused if you want to reduce the risk of viruses or othermalicious software, and to check the authenticity ofsoftware when you download and install software to yourdevice.Tip: When you add a new certificate, check itsauthenticity.View certificate detailsYou can only be sure of the correct identity of a serverwhen the signature and the validity period of a servercertificate have been checked.To view certificate details, open a certificate folder, andselect a certificate and OptionsCertificate details.One of the following notes may appear:ವ Certificate not trusted — You have not set anyapplication to use the certificate. You may want tochange the trust settings.ವ Expired certificate — The period of validity has endedfor the selected certificate.ವ Certificate not valid yet — The period of validity hasnot yet begun for the selected certificate.ವ Certificate corrupted — The certificate cannot beused. Contact the certificate issuer.Certificate trust settingsTrusting a certificate means that you authorise it to verifyweb pages, e-mail servers, software packages, and otherdata. Only trusted certificates can be used to verify servicesand software.105 Security and data managementCyanCyan MagentaMagenta YellowYellow BlackBlackCyanCyan MagentaMagenta YellowYellow BlackBlack