DavidR
7
If the file is back in the original location, then it should be OK to remove the copy in the chest.
This is why it is important to move files to the chest rather than delete, as detections can change, if it is a false positive the detection will be corrected. So subsequently scanning a file from within the chest and it no longer detected you can use the Restore option from the chest. Avast would know about them as first they were considered infected, but not now, so the detection signature has been changed (an indication of an FP).
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For the future - You could also check the offending/suspect file/s at: VirusTotal - Multi engine on-line virus scanner and report the findings here, post the URL in the Address bar of the VT results page. You can’t do this with the file securely in the chest, you need to Open the chest and right click on the file and select ‘Extract’ it to a temporary (not original) location first, see below.
Create a folder called Suspect in the [b]C:[/b] drive. Now exclude that folder in the File System Shield, Expert Settings, Exclusions, Add, type (or copy and paste) C:\Suspect*
That will stop the File System Shield scanning any file you put in that folder.