According to Yahoo blogger Christopher Null: The Working Guy

Reader Jeffrey writes: All of a sudden, I am receiving an inordinate amount of "bulk" email in my Yahoo account. Many of the identical emails are sent day after day, which I delete without opening. My question is this: Assuming they are sent to me automatically, would there be any point in opening them and responding with a note that I am not interested, and that I would like for them to discontinue sending them to me. Of course, if there is an attachment, I would not open them under any circumstance.

First off, some slight clarification: There is outright spam and there is commercial, bulk email, and though the line can be blurry, following careful instructions can often eliminate the latter without you having to rely on your spam filter or delete button.

First you need to determine what kind of junk mail you have. Is it being sent by a company you've ever done business with, or something you might have signed up for in the past, however long ago? Most commercial mail being sent by legitimate companies will have an unsubscribe link at the bottom, and though those links can take a few days (up to 10 in some cases) to go into effect, if you follow the instructions to unsubscribe from a mailing list (be sure to complete the transaction and read what to do carefully so you don't miss anything) the messages should stop.

The problem of course is that with true, unsolicited spam, those links don't work. In fact, many pundits feel that clicking them only validates your email and will end up getting you more spam. I doubt this is really the case—once you're on the list, you're on the list—but the basic point is valid: Clicking unsubscribe links on spam is a big waste of time.

As for sending email replies, that's an even worse idea: Virtually all commercial junk mail and unsolicited spam is sent from an unmonitored email address. Actually typing a note to reply is an even bigger waste of time since you have to type something up and no one will ever read it, and since you're likely to get an email bounceback, you're actually creating even more spam for yourself to deal with later. (As well, since a lot of spam is sent using a forged "from" address, you're probably creating spam for some other poor sap, too.)

So no, don't ever reply via email to a spam message, though we all appreciate your thoughtful and considerate approach to dealingwith the matter.