Do I need McAfee or Norton or is Defender enough virus protection?

Although Norton (Symantec) and McAfee are as good as any other well known anti-virus program, they require numerous services and running processes that consume a lot of system resources and often results in complaints of high CPU usage. Anti-virus software components insert themselves deep into the operating systems core where they install kernel mode drivers and resource heavy processes that load at boot-up. Those issues plus the cost factor are the primary reason many folks look for a free alternative. IMO, Norton and McAfee are better utilized in an Enterprise system environment protecting many client computers.

IMO Windows 8/10 Defender is just as good as any other free antivirus solution (and probably easier to use for the novice) without bundled toolbars or nagging popups.

• Is Windows Defender Good Enough
• Microsoft: Our commitment to Microsoft antimalware

Although Windows 8/10 Defender provides some anti-malware protection...it is weak, meaning it does not provide comprehensive protection and cannot prevent, detect and remove all threats at any given time. This is true for most anti-virus solutions. Anti-virus and anti-malware programs each perform different tasks as it relates to computer security and threat detection. Essentially, they look for and remove different types of malicious threats.

In simplistic terms, Anti-virus programs generally scan for infectious malware which includes viruses, worms, Trojans, rootkis and bots.

Anti-malware programs generally tend to focus more on adware, spyware, unwanted toolbars, browser hijackers, potentially unwanted programs and potentially unsafe applications.

Anti-virus and Anti-malware solutions with anti-exploitation features protect against zero-day malware, drive-by downloads, exploits and Exploit Kits.

Therefore, you need both an anti-virus and an effective anti-malware solution for maximum protection. Please read Supplementing your Anti-Virus Program with Anti-Malware Tools for information about trustworthy and effective anti-malware programs which can find and remove adware, spyware and potentially unwanted programs.

The new Malwarebytes 3.0 combines their previous Anti-Malware, Anti-Exploit, Anti-Ransomware programs along with malicious website protection into one product which is just called "Malwarebytes". Malwarebytes 3.0 can be used to replace your existing anti-virus or serve as an adjunct anti-malware solution to strengthen your protection since it lacks some constructs that a traditional anti-virus application employs. The Development Team continues to provide support for those who choose to use a traditional third-party anti-virus solution together with Malwarebytes.

Windows 10 Anniversary update includes a Limited Periodic Scanning feature to provide additional protection against malware for those using a third party anti-virus program as their primary protection.