Or - Send the sample to avast as a False Positive:
Open the chest and right click on the file and select 'Submit to virus lab...' complete the form and submit, the file will be uploaded during the next update.
- In the meantime (if you accept the risk), add the full path to the file to the exclusions lists:
File System Shield, Expert Settings, Exclusions, Add and
avast Settings, Exclusions
Restore it to its original location, periodically check it (scan it in the chest), there should still be a copy in the chest even though you restored it to the original location. When it is no longer detected then you can also remove it from the File System Shield and avast Settings, exclusions lists.