Opera Help and Support

The settings in Tools > Preferences > Advanced > Network and Tools > Preferences > Advanced > Cookies determine how Web servers handle and monitor your net activities.Referrer loggingSome Web sites register the site that referred you to them. This information can be used to control content by delivering documents that have some bearing on the site that you came from. If you prefer not to allow a Web site to know where you were before visiting it, especially if you were on a local, secure, or restricted site,...

E-mail securityIf you leave the authentication type for your login as "Auto", Opera will try the most secure authentication available and then work its way down the list should the first type fail. The authentication types available to you will depend on the mail server. Note that this will not encrypt your actual mail data, only your login.Adding certificates in OperaReputable on-line merchants have their public keys signed by authorities, which are trusted security firms. These firms issue digital certificates that contain...

When you send or receive information from a site where Opera's icon displays "Secure", Opera and the Web site use a secret one-time key before sending the information. When you entered the secure page, Opera and the Web site used public keys to agree on that secret key. That is called a handshake. The key encrypts all the information sent and is used for this session only.The level of encryption depends on the available key space, which means the number of possibilities when generating keys. The more possible keys, the higher...