Does Avast scan all drives when run from ubuntu on a usb?

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1

My father has a virus on his windows PC that won’t allow us to do anything in the windows installation.
I have booted into a portable Ubuntu installation with avast free installed. I have selected the “THourough” option and the “test archives” option.

As best I can tell it does not scan other drives, just the one that the OS is running on. Is that the case?

And does anyone have any suggestions to solve this issue?

2

I think you need to mount the Windows installation and be running Linux. Within Linux and with the Windows mounted, yes, you can scan it.
Otherwise, I’ll suggest a Rescue CD (there are quite some freeware) to scan the computer.