Microsoft’s little-known anti-virus tool

By J. Carlton Collins

Q. Which free anti-virus solution do you recommend we use with Windows 8.x?

A. Microsoft provides a free built-in anti-virus solution called Windows Defender. This solution was initially an anti-spyware program included with Windows Vista and Windows 7; however, beginning with Windows 8, Windows Defender has been upgraded to also include anti-virus protection. To avoid upsetting competing anti-virus software companies, Microsoft does not publicize Windows Defender much, and as a result, many CPAs are unaware of its existence. Further, Windows Defender is turned off when full or trial versions of rival anti-virus solutions are installed (or preinstalled) on a Windows computer; therefore, you may first need to uninstall any existing anti-virus products (even trial versions) before you can activate Windows Defender.

Once you have uninstalled any existing anti-virus programs, you can activate Windows Defender from the Windows 8 Control Panel by selecting Windows Defender to display the dialog box pictured below.


Click the option labeled click here to turn it on. Then in the following dialog box, click the button labeled Check for updates now. Once the updates are complete, Windows Defender will begin protecting your computer from malware such as spyware and viruses. The Windows Defender main screen is pictured below.


Comments About Windows Defender:

1. Free Windows 7 and Vista protection. The anti-virus component included in Windows Defender is now also available for free to protect Windows 7 and Windows Vista computers. To use this on Windows 7 and Vista computers, download the applicable version of Microsoft Security Essentials at

2. For Windows XP users. Microsoft Security Essentials was previously available for Windows XP; however, effective April 8, 2014, Windows XP is no longer supported by Microsoft, and therefore this security option is no longer available on that platform.

3. Weak reviews. Be aware that some independent reviewers of anti-virus solutions rank Windows Defender (and all free anti-virus solutions) as weak compared to many anti-virus products you have to pay for. For example, in its August 2014 report, AV-Comparatives ranked Windows Defender below 22 other fee-based anti-virus products; according to this report (available at, Avira, Panda, and Trend Micro scored as the top three anti-virus programs for this particular test period. The lesson is that anti-virus programs you pay for are stronger than their free counterparts.

J. Carlton Collins ( is a technology consultant, CPE instructor, and a JofA contributing editor.

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