issue with email protection

Hi everybody!
I have my first issue with avast Avast Security for mac Free:
I received a message every 30 minutes on the right side of desk in with this message:
Infection Blocked!
infection: JS: Agent-DVX (TRJ)
File: PartNo_0/PartNo_0/PartNo_0/PartNo_0/fattura/fattura.pdf.js
Process: Application/mail.app/contents/macos/mail

What’s the matter?What can I do to stop it?

Thanks.

Probably best to post this in the Mac sub-forum - Avast Mac Security.

Probably a sync problem

Does avast quarantine the mail?
Access your mail account from web mail and make sure detected mail is deleted, then clear cache in your mail app/mail client and reboot