Q Recently I've been unable to send e-mails from my home e-mail address. In addition, my incoming e-mail contains several notices of undeliverable e-mails that I didn't send that are addressed to people I don't know. I suspect that my computer is infected by some malicious software and is being used to send spam e-mail -- and that those that are undeliverable are being returned. What should I do?

JOSEPH CAMPBELL, BURNSVILLE

A I agree that your PC has been taken over by hackers and is being used to send spam.

The fact that you aren't able to send e-mails from your home account supports this theory, since it indicates that your Internet service provider believes you are spamming and has temporarily blocked your ability to send e-mail to anyone.

I suggest you download and run the free version of security program Malwarebytes (go to tinyurl.com/cwbd73f and click "free download.") If that doesn't work, try Windows System Restore to eliminate recently installed software (see tinyurl.com/y9q9apj and tinyurl.com/ykgps6.) Then call your Internet service provider; explain what happened and what you've done to fix it. If your PC is clean, you'll be allowed to send e-mail again.

Q I've recently received a lot of spam, including some that appears to be from people that I know -- except that the messages come from the wrong e-mail address. How does a spammer use a familiar name with a fake e-mail address and send it to me?

Also, is there a way to find out the identity of the people who send spam e-mails? I've read that the e-mail address of the sender is not always accurate.

GINGER BRAMLETT,

ROCKWALL, TEXAS

A The bogus e-mail that appeared to be from your friend, but came from the wrong e-mail address, is from a spammer who is trying to trick you into opening the e-mail.

Why did this happen? Your friend's e-mail may have been hacked and his or her address book stolen, providing the spammer with a host of addresses where an e-mail bearing your friend's name might be opened by the recipient.

It's hard to find out who actually sent spam, because originating e-mail addresses are easy to fake.

I suggest you send these e-mails to your spam filter so that you and others may be spared at least some spam in the future. In addition, your Internet service provider allows you to block spam that comes from a specific domain name (the part of the e-mail address that follows the @ symbol, such as Yahoo.com). See tinyurl.com/cxmq4m7.

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