Many people would like POPFile to scan email before it comes down to their machine to get rid of spam before it is ever downloaded! This could be handy if you are on a slow connection…in a hotel perhaps.
Unfortunately, for POPfile to make the determination that a message is spam, it has to download the message. Once POPFile has downloaded the message, it can classify it according to any bucket you create, including a spam bucket. It is up to your email client to move mail that POPFile has classified into another folder.
Once the email has been classified by POPFile, your email client can, for example:
In other words, think of POPFile's classification and your mail client's rules as symbiotic–each helping the other to help you.
If you can determine some very specific conditions where you are 100% certain, you can set rules in your email client, (e.g. Outlook) that automatically delete messages completely. Then messages do not go into the Deleted Items, they are gone permanently. This doesn't solve the otherwise unnecessary consumption of bandwidth, but you don't have to look at those messages either.
In Outlook, you can use the Permanently delete action and in Outlook Express use the Delete it action when you make your rules.
WARNING: If you delete messages they will be gone permanently so do this with great caution. Moving the message to a temporary folder allows you the chance to inspect the email for accurate classification.