Every other week or so, FOXNews.com tries to solve your most vexing technology-related problems. Send your questions to TechQuestions@foxnews.com and we'll reply to selected ones in our next installment.

I asked my Canadian-born wife if they had an equivalent to the 4th of July in Canada.

When she told me that they didn't, I asked her, "What do they put between the 3rd and the 5th?"

Anyway, to all my friends north of the 49th parallel (including a bunch of fellow Nerds!), Happy Canada Day!

• Click here for FOXNews.com's Personal Technology Center.

Cutting the Wires

Q: I subscribe to Cox Communications' high-speed cable-modem service. What equipment do I need in order to install Wi-Fi throughout my home?

A: A Wi-Fi setup in your home works much the same way as a cordless phone: There's the part that plugs into the phone jack and sends the signal, and one or more handsets that receive the wireless signal.

In the case of a wireless network, you will need a wireless router — which will plug directly into your broadband modem — and each computer will need a wireless adapter or network interface (if one isn't already built in).

Microsoft has a basic tutorial here.

Pay special attention to the three things Microsoft says you ought to configure:

— 1. The SSID, or name of the wireless network ("BriggsLAN," for example, or "GetYourOwnDarnedBroadband"). It can be any name you want. You can even specify that it not be broadcast (effectively making your network invisible) but it's a little more difficult to connect computers to it.

— 2. You should turn on encryption. It comes in several flavors — WEP will allow more devices, especially older ones, to connect, but WPA is the most secure. For the former, www.wepkey.com will take a passphrase and convert it into a 64 or 128-bit WEP key if your wireless router doesn't do it for you.

For the latter, pick a phrase of at least 14 characters, capitalize the first letter and change some of the vowels to numbers. For example, the first 4 words of the Declaration of Independence are "We hold these truths ...".It could be modified to "W3 h0ld th3s3 truths" to make a fine, easy-to-remember-but-hard-to-crack WPA passphrase.

— 3. Change the router's password.

The installation disk that comes with the router should handle the rest of the configuration chores for you.

Windows XP Death Watch Update

In a story that appeared on NewsFactor last week, Microsoft announced that support for Windows XP will be extended to April 2014.

According to the NewsFactor story, Microsoft Vice President Bill Veghte wrote, "It's true that we will stop selling Windows XP as a retail packaged product and stop licensing it directly to major PC manufacturers."

"But," he said, "customers who still need Windows XP will be able to get it."

• Click here for more on the 'death' of Windows XP, and

• Click here to read how you can still get it pre-installed on some machines anyway.

What Happened to My Sound?

Q: My audio has disappeared! I've checked the speakers (integrated into the monitor) to make sure that they aren't muted, I've checked the sound icon in the taskbar and the volume is turned up. But I get no sound. All the cables are plugged in. What happened, Mr. TechQuestions?

A: The above was from my wife of 34 years. And I can honestly say they have been 10 of the happiest years of my life! She hates that joke, but she is a saint! She would have to be, to put up with me this long!

The answer is that an update from Microsoft killed the sound in some systems — specifically, sound cards which use the AC '97 codec.

How do you tell? Right-click on "My Computer" and select "Manage." Scroll down to "Sound, video and game controllers" and expand the tree (click on the little plus sign).

Look for something that says "AC '97." Right-click that and choose "Properties." Click on the tab marked "Drivers." Click on the button which reads "Roll Back Driver."

Problem solved.

Incidentally, driver updates normally show up as "optional" on the Windows Update Web site. I tend to install them even though they're optional, but it sometimes gets me in trouble.

A good rule for the normal user is, "If it ain't broke, don't fix it." Meaning: Only install optional patches from Microsoft if you're having a problem.

Of course, my personal philosophy is, "If I can't fix it, it probably wasn't broken." But that's grist for another mill.

How Do You Say 'Is That So?' in German?

Q: I'm sorry to inform you but there are a zillion hackers out in cyberspace and they aren't playing by your rules. In spite of me having a router with a private number, they still get through.

I am constantly bombarded with sob stories that will make me a rich man overnight. I get others that will make my 75-year-old wife extremely happy if I will only use their medicine. I've had offers from casinos that will bankroll me with up to $500 if I join. I've had job offers if I will do money laundering.

And for some unknown reason they all can through the router without a proper e-mail address.

Complaints to my ISP do not help either. They claim that everything checks out OK on their end and insist that the problem is by me.

Your interesting theory is just that. Only a theory. Nothing more.

A: One of the problems in writing this column is trying to strike a fair balance between Normalspeak and Nerdspeak.

In my last installment, I described how a router protected a home network from "the bad stuff." Certainly my German reader (according to his e-mail address) is correct that spam is "bad stuff" — I was, however, referring to malware, not spam.

Spam is like the junk mail that your friendly neighborhood letter carrier delivers each day (and which you carry into the house yourself).

Malware is more like the hoodlums who break into your home, steal all your valuables and spray-paint epithets in green fluorescent ink all over your walls.

A router, in conjunction with good anti-virus and anti-spam programs, protects you from malware. But unless you have a firewall appliance or UTM (unified threat management) box in place, spam gets through.

Spammers get through in exactly the same way that telemarketers do — for a given area code and prefix, they start with "0000" and dial every number through "9999." You get called even though your number is unlisted.

In the case of spam, they start with letter-and-number combinations (for a given domain) beginning with "a" and try every one through "z."

If they don't get an "invalid address" rejection from your ISP, they know the address is good — and they remember it and sell it to other spammers.

Thus, it isn't long before they discover that guy547@myISP.com is a valid address — right after they learn that "guy546" and "guy 548" are both invalid.

Until the various providers of e-mail can get their collective acts together and agree on some sort of authentication protocol, the answer is to put one or more spam filters in place.

If you have a Gmail account, there is a "Spam Folder," where some of the spam is trapped and held (up to 30 days, for your review). The same is true if Yahoo! or NetZero is your provider.

Also, the e-mail client you are using may have some spam-filtering capabilities. Microsoft Outlook, for example, has a "Junk E-mail" folder where it deposits e-mail it thinks is spam.

I get 250 or more pieces of spam every day of the week — and more on weekends, since the spammers seem to think I'm more likely to read and respond on my days off.

Yet I only see 1 or 2 pieces each week. Why? The solution I have used for several years can be found at www.spamarrest.com.

Spamarrest works by downloading e-mail from all of your accounts and forwarding to your computer only those from senders on your approved list (your "whitelist").

It has several options for adding senders to the approved list.

You can peruse messages in the "Unverified" folder, check those you wish to see and click on "Authorize." You can specify an entire domain (for example, by allowing e-mail from anyone at MyEmployer.com).

Messages can be blocked ("blacklisted") in much the same way.

When a real, honest-to-goodness, human being sends you e-mail, she or he is sent a polite message indicating that the message has been held but can be unblocked if the human will kindly type the numbers and letters he sees in the displayed graphic.

Spamarrest has a 30-day trial for both business and individuals. Give it a try!

Guy R. Briggs is a member of the Nerds On Site international IT service team and is based in Los Angeles.

Got questions about computers and technology? Send them to TechQuestions@foxnews.com and we'll answer selected ones in our next installment.

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