Joe Shikonya of La Crosse, Wis., wonders if he should change his e-mail address to avoid junk e-mail, or spam. And is there some way to track down the people who send it?

Dennis Volz of Parker, Colo., wonders how someone could send spam to a secondary e-mail account that he hasn't even used yet. Is his internet service provider recycling old e-mail addresses, or disclosing new e-mail addresses to the public?

Let's start with this premise: You can't stop spam. You can only try to reduce the amount of spam you receive, and to route what you do get to your spam folder instead of your inbox.

The best way to accomplish those things is by labeling unwanted messages as spam (so your e-mail provider can try to block them in the future) and by being careful how you handle e-mail.

So, which strategies will help you achieve those goals and which ones won't?

Changing your main e-mail address to avoid spam is probably fruitless. You'll go to a lot of work to tell every person and business you deal with that you've got a new address, and in a couple of weeks you'll be getting a lot of spam again.

Can you track down the people who send spam and make them stop? No. They are always on the move, changing their e-mail addresses and internet service providers so they can remain anonymous.

Can you find out how someone sent spam to a brand-new e-mail address you haven't even used yet? Yes, but knowing won't help you. Spammers can find your new address by using a "dictionary attack," in which many potential e-mail addresses are tried at once to find a few to which spam can be sent.

These spam messages are then sent out by the millions. If an address doesn't exist, the message will bounce back to the spammer, who will then delete that address from his or her mailing list. But if the spam is sent to your new, never-used e-mail address it will be delivered and the spammer will know to send that address more spam in the future.

So, if these spammers are so smart, how can you defeat them? Here are some ways:

Never click on anything in a spam message. Just send it to the spam folder.
If you think an e-mail is spam, don't even open it. Many spam e-mails contain a link to a tiny image file that's located on a distant server. When you open the spam e-mail, that image downloads from the server to your computer. That gives the spammer your IP (internet protocol) address and tells him or her that you might open other spam messages in the future.
If someone sends you a suspicious e-mail, don't try to unsubscribe from it. If you try to unsubscribe, a spammer will think you've been fooled into believing his or her spam is legitimate e-mail – and send you more spam.
Be careful if you post an e-mail address on social media or websites. Spammers "harvest" e-mails by searching websites for the "@" symbol. So, change the spelling or spacing of your address. Turn "WillSmith@gmail.com" into "WillSmith at Gmail.com" or "Will Smith at Gmail."
Use a disposable e-mail address that receives e-mail and forwards it your real address (see tinyurl.com/y2h7ns6f). If you get spam from a disposable address, just turn off that address and use a different one. While this strategy isn't for everyone, it might help those who sign up for newsletters or who must disclose their e-mail addresses in order to buy goods online. Because disposable addresses are typically used only once, you'll always know which newsletter or website failed to protect your e-mail address and thus caused you to receive spam.

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