Over half of Windows 7 PCs have no antivirus installed

Microsoft's latest security report contains several interesting statistics on Windows antivirus usage. Over half of all PCs running Windows 7 have no antivirus software installed or have it turned off. The situation's not much better on newer versions.

The findings were reported by Microsoft in volume 22 of its regular Security Intelligence Report, covering the first three months of the year. The data is collected by assessing telemetry information from millions of Windows Vista, 7, 8, 8.1 and 10 computers worldwide. Only machines that have explicitly opted to report telemetry stats are included.

In the security software use section of the report, Microsoft revealed how many Windows computers are actively protected against digital threats. It found that of devices that aren't protected, those running Windows Vista or Windows 7 "predominantly report" having no antivirus software installed at all.

Over 50 percent of unprotected machines using each operating system do not have an antivirus product installed. Of those that have one installed, the vast remaining majority either have it turned off or haven't updated it.

On Windows 8, the situation is marginally better. A lack of antivirus software accounts for just 5 percent of all the unprotected cases because Windows Defender is installed by default on Windows 8 and up. The biggest cause of ineffective antivirus on this version is having the installed protection turned off. Out-of-date virus definitions are also a significant contributor.

Windows 10 shows different statistics again. A very small number of PCs have no antivirus software installed. The majority of "unprotected" cases are caused by the active antivirus software being "snoozed," temporarily disabling it. This suggests that Windows 10 users are more likely to have installed, enabled and updated their antivirus software. They then turn it off during use though.

On a global scale, 73 percent of assessed Windows computers were effectively protected during the survey period. Devices in Finland were the most likely to be secured at 92.2 percent of PCs, followed by Portugal (90.3 percent) and Denmark (90.2 percent). At the other end of the list, Peru, Venezuela and Turkey were the least likely to be protected at 78.3 percent, 80.4 percent and 80.6 percent respectively.

The publication of the report is timely for Microsoft. It was recently forced to settle a lawsuit with Russian antivirus provider Kaspersky Lab over claims it was deliberately disabling and disadvantaging third-party products on Windows 10.

The survey data appears to indicate that Microsoft's inclusion of Windows Defender as a default fallback was based on a genuine need from a security standpoint. Kaspersky dropped the case after Microsoft agreed to make concessions to third-party antivirus providers in the upcoming Windows 10 Fall Creators Update.