Mcafee.com/activate- Antivirus software is a program that detects and blocks viruses from entering your computer. It also kills or quarantines any viruses that have penetrated the firewall. McAfee Antivirus blocks malicious websites, rootkits Trojans, viruses, and phishing scams. It displays in-browser information about the threats it blocks. McAfee Antivirus displays the IP addresses associated with the threat. This allows tech-savvy users to avoid sites that are connected to these addresses.