A rootkit is a stealthy type of malicious software (malware) designed to hide it existence from the Windows operating system as well as hide from Antivirus and AntiMalware scanners. If your computer continues, and I’m talking every few minutes or hours, to become re-infected with Trojans, Viruses, or Malware then you might have a rootkit. Rootkits can remain on your computer and re-infect the computer even if you perform a system restore, reload your operating system, or use a manufactures factory installation media.
Malware-Bytes Rootkit scanner – An excellent utiity that is small, easy to use and is one of the best rootkit scanners available.
Kapersky Anti-rootkit utility – TDSSKiller is a free utility provided by Kapersky that will scan for Malicious rootkit software on your computer.
McAfee now provides a Rootkit scanner – A Rootkit is basically a malicous program (virus) that hides itself by using invalid WIndows characters – Microsoft will not let you create a file or folder with characters – !@#$%^&*()….). Most antivirus scanners can not detect rootkits.