Okay I downloaded a few mods for Skyrim from the Nexus, and in my file manager I use the context menu to scan the downloaded files. And for some reason Avast decides to start scanning the entire drive instead of just the files I selected to scan? ??? I stopped that scan and tried again … and the second time it just scanned the files I selected? ( As it should have done the first time. )
I use the context menu to scan the downloaded files.Files are already scanned by avast when downloaded and saved to disk (should be unless there is a bug)
for a second opinion, check file(s) at virustotal.com then they are scanned with 50+ AV engines
The scan bug, i have no idea …
Yeah I know downloads are scanned when downloaded, but it is a force of habit that I apparently can not seem to unlearn so far. 
I scanned with MBAM … did a Full scan with Avast, and after I saw your post I scanned the downloads with Virus Total and nothing bad was shown. ( As was to be expected I guess. )
That scan bug never happened before, and I tried a few other downloads and the context scan ran as was intended. I have absolutely no idea why that scan bug happened?
Can you reproduce the issue?
Not at the moment, but if or when it happens again I will post it in here. I have no idea why or how it happened, so I now just have to wait and see if it happens again. ( But no matter what it is a weird thing to happen. )
Is it possible that you accidently did a right click on the folder and then selected the scan option ???
No because you can see in the screenshot that I was in the Downloaded Software folder, and I only selected the files that I hat downloaded. I am 100% certain about that.