To get rid of the above message, you can use Group Policy to allow Defender to scan files on the network.ġ. If you feel in need to scan a NAS, you may use the fixes given below to allow network scans. I guess, that's the reason, why Microsoft disables network scan in defender by default. If multiple clients in a network – and also the AV software on a server, starts to scan (the same) network files, there is a lot of (senseless) traffic. But Microsoft don't recommend network scans. Note: Below are a few hints, given as fixes, to avoid the notification, by allowing network scans. That's what I conclude from the hint of Jens in this comment and from the hints given below.

The message is not wrong and makes sense with today's knowledge (from the following sections) – because it will be displayed when a user-defined exception was found for the scan OR when the standard default of not scanning network files was followed. I feel it's pity that Microsoft hasn't documented this somewhere and doesn't differentiate in its notification. Something seems to have changed Microsoft's behavior some time ago. The message from the Defender occurs, because the Defender doesn't scan network files anymore by default. Since the affected users did not define exclusions for scanning, much indicated a problem with the network scan. I had covered the case in more detail in the blog post Windows 10: Defender skips elements during scan. Windows Defender skipped an item due to exclusions or network protection settings.

Although the scan is successful, at the end of the process the virus scanner reports skipped items during the scan. Since several weeks some Windows 10 users have been experiencing a strange effect when scanning their systems using Windows Defender.

Windows defender scanner