Mail shield

Hello,

I get several times a day a popup message:

Infection Blocked!
Avast Mail shield has blocked a threat
Infection: MW97:Downloader-Q[Tri]

I would like to remove this email message but the weird thing is that when I search for that particular message in my online accounts (thus not on the mac local email client as Avast would block it) I cannot find that particular message.

Anyone any idea?

Thanks!