Our free software, Sophos Anti-Rootkit scans, detects and removes any rootkit that is hidden on your computer using advanced rootkit detection technology. Rootkits can lie hidden on computers and remain undetected by antivirus software. Although new rootkits can be prevented from infecting the system, if you had any rootkits before you installed your anti-virus, they may never be revealed. Removing rootkits without compromising system integrity is particularly challenging and needs to be done with care.