I think it does what you want. I use it to delete or bounce junk mail before downloading from the server.
For reasons that I don't want to go into, I want to be able to bounce email from Yahoo to its sender. I am running on Vista Home Premium on a Dell.
At this point, it is impractical for me to change email services.
I downloaded Mail Guard, but I can't get it to work because i get a screen message that says that my Pop mail isn't integrated with my smtp or some such thing which means absolutely NOTHING to me. There's some rudimentary direction for this program, but not much.
There's also Mail Washer which I understand will allow me to bounce an email back to the sender as undeliverable. I haven't tried that yet. I get the feeling that my limitations in understanding how to hook the frammazamma into the ntsrp pimpdad protocol is severely hampering my efforts.
For clarification purposes, I will stress that i am not looking for a spam filter or to manage undeliverable mail. I just want to bounce an email back to the sender as if it were undeliverable. Is there something that installs, configures itself nearly completely without my having to be a brain surgeon?