A possible cause of the user being redirected to unexpected websites is that the localhost file entries have been modified by malware or hackers to point to malicious or unwanted websites. The localhost file is a text file that maps hostnames to IP addresses and can override DNS settings. By examining the localhost file entries, a technician can identify and remove any suspicious or unauthorized entries that may cause the redirection issue.
Enabling firewall ACLs may not resolve the issue if the firewall rules do not block the malicious or unwanted websites. Verifying the routing tables may not resolve the issue if the routing configuration is correct and does not affect the web traffic. Updating the antivirus definitions may help prevent future infections but may not remove the existing malware or changes to the localhost file. References: CompTIA A+ Core 2 (220-1002) Certification Exam Objectives Version 4.0, Domain 1.3