To know if a file is a false positive, please submit it to
VirusTotal and let us know the result. If it is indeed a false positive, send it in a password protected zip to virus@avast.com
Please, mention in the body of the message why you think it is a false positive and the password used. Thanks.
Other possibility is
JOTTI. VirusTotal and Jotti both have file size limits 10 and 15MB each.
As a workaround, you can add these files to the
Standard Shield provider (on-access scanning) exclusion list.
Left click the 'a' blue icon, click on the provider icon at left and then Customize. Go to Advanced tab and click on Add button...
You can use wildcards like * and ?. But be carefull, you should 'exclude' that many files that let your system in danger.
After that, please, periodically check it - scan it into Chest, right clicking the file - there should still be a copy in the chest even though you restored it to the original location. When it is no longer detected as being infected then you can also remove it from the Exclusion list.
Merry Christmas!
