The resident scanner is the one that monitors files on access and you haven’t added it to the Standard Shield, see below. See the note in the Program Settings, Exclusions (your image), ‘except for resident protection.’
You could also check the offending/suspect file at: VirusTotal - Multi engine on-line virus scanner I feel virustotal is the better option as it uses the windows version of avast (more packers supported) and there are currently 30 different scanners.
Or Jotti - Multi engine on-line virus scanner if any other scanners here detect them it is less likely to be a false positive. Whichever scanner you use, you can’t do this with the file in the chest, you will need to move it out.
If it is indeed a false positive, add it to the exclusions lists (Standard Shield, Customize, Advanced, Add and Program Settings, Exclusions) and 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 Standard Shield and Program Settings, exclusions.
I couldn’t translate the Note: in your image, you could Start a new Topic reporting this translation inaccuracy, suggesting a better French description for the Note.
I would suggest you confirm the detection at VirusTotal, etc. to ensure it is a false positive detection. If so you should send a sample to avast for analysis and correction of the VPS.
Send the sample to virus@avast.com zipped and password protected with password in email body and false positive in the subject.
Or you can also add the file to the User Files (File, Add) section of the avast chest where it can do no harm and send it from there (select the file, right click, email to Alwil Software). No need to zip and PW protect when the sample is sent from chest.