Why won’t Avast scan these files?
QWhen I scan my computer using Avast Free, it tells me that it was unable to scan some files. The warning box that appears says this is because the files in question are passwordprotected. That’s as may be, but what or whose password would this be? It’s not mine, at least so far as I know. Is this normal? Is there anything I can or need to do about it? Michael Grinter
AIt is normal and there’s probably nothing to worry about — but there are things you can do to deal with the annoyance.
This message is most likely appearing because Avast is encountering encrypted or compressed files that relate to software you have installed. Software developers use these techniques to keep their downloads and installation files safe, and as small as possible. These are typically deleted automatically once the program installation is complete, but this won’t always be the case — so you’ve probably got a few remnants on your hard drive.
First, launch Control Panel (via Windows key+x in Windows 10) and then click ‘System and Security’. Next, under Administrative Tools, click ‘Free up disk space’. In the Disk Clean-up box that appears, tick Downloaded Program Files and Temporary Internet Files, then click OK followed by Delete Files (see screenshot).
If Avast continues to show alerts, make a note of the filenames and locations, and then search for them on Google for more information. You might then decide to remove them manually, using File Explorer (or Windows Explorer in Windows 7), or have Avast ignore the particular file type. That might sound unwise but most compressed file types aren’t themselves inherently dangerous — it’s their contents you have to worry about. Indeed, in common with other security programs, Avast ignores many compressed file types, other than those that are able to ‘self-extract’.
To make changes to the file types Avast skips, first click Scan and then select a scan type from the dropdown menu. Now, below Avast’s Start button, click the Scan Settings link. Then, in the left-hand pane, click Packers. Keep the top two boxes ticked (‘Self-extracting...’ and Droppers), but then feel free to remove ticks from the offending file types below. If the contents of such files ever extracted you’ll still be protected, as Avast will scan them in real time. Click OK to save your changes.