To help identify zero-day malware, Bloodhound technology disassembles and scans application code for possibly malicious instructions. Norton can revert Internet Explorer homepage hijacking attempts and block advertisements. Users are warned of unauthorized changes to Internet Explorer's homepage, and given an option to revert such changes. Advertisement blocking rewrites a website's HTML to prevent advertisements from being displayed. E-mail filtering scans POP3 mail for spam. It can be configured using either a blacklist or a whitelist. Users can also correct Norton's classification of e-mail on a individual basis. Parental controls, bundled with this release, allow users to block specific sites, block certain programs from accessing the Internet, and restrict newsgroup access. Norton can block the transmission of confidential information. Users can enter information which are not to be communicated via instant messenger, e-mail, or webforms. 