While the native Windows antivirus scores very well in detecting and protecting against threats when the computer is online, this rate drops dramatically when offline. Without an Internet connection, Windows Defender becomes one of the least effective antiviruses in the comparison, along with Panda and Trend Micro. On the contrary, G DATA, VIPRE, Total Defense, Bitdefender, Avast, AVG and Avira remain extremely efficient offline.
« We suggest that vendors of cloud-intensive products notify users appropriately in the event of loss of cloud connectivity, as this can significantly affect the protection provided. », publishes AV-Comparatives.
Windows Defender is also one of the worst antiviruses tested in terms of false positives, far more than most of its competitors. According to the AV-Comparatives study, only Panda and K7 do worse. The good performers are Avira, ESET and Kaspersky, which did not trigger any false positives on the sample they processed.