So, I noticed that avast! does not do Automatic USB scans so i am kind of suggesting of adding this feature. AVG has this feature but avast does not has this feature, avast! is clearly better than AVG tho its just that avast! does not do automatic USB/External Hard drive scans.
Avast scans activity - plugging in an external drive or USB doesn’t necessarily mean activity.
Automatic scans of an external drive or USB, isn’t really a great idea as for the most part the files on it are dormant, when you try to run one it will be scanned by the file system shield. That is the idea of a resident on-access scanner.
Scanning an external drive when plugged in could well take a very long time - depending on your system spec you could be waiting around for some time waiting on the scan to complete.
So lets say you have a full 1TB USB drive and and plug it in, you want avast to auto scan all 1TB when plugged in?.. that may take some time
avast realtime protection will scan any file on the drive when you access or open a folder …