JFLS41:
How does that MAILWASHER send stuff back? If your ISP's mail server has already accepted the spam, then you pretty much can't send it back. 90% of spam these days comes with a return address randomly chosen from the spammer's mailing list, so sending anything back to the return address means you're just sending spam to someone who isn't the spammer. How would you feel if people sent email "back" to you when a spammer happens to pick your email address for the return on spam that is going to someone who happens to be running that program?
FYI, I am active in a couple major anti-spam working groups. This kind of thing has been discussed for years, and the concensus switched about 4-5 years ago to not sending anything back after the original delivery connection is closed (which is in the past once you are picking your mail up from your mailbox at your ISP). More recently, I've been seeing cases of accounts being suspended because of these send-backs that are misdirected.
Now I don't know exactly how MAILWASHER really works because I don't use it. I'm only speculating. But to avoid some of the dangers, it is important to find out these details.
renosteinke:
That's a prime example of why I use a different email address for every place I sign up. if it turns out one is really releasing addresses for spamming, I can just that one off. Of course not everyone has the ability to do this even if they get a dozen free email addresses from their ISP (shutting one off is often a big hassle). By owning my own domain and running my own mail servers, I do have that ability. A few ISPs do offer that level of service to their customers, and even without having to own a domain (though that does help a lot).
