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've previously written about the 411 service that every computer on the Internet uses to obtain IP addresses from the easy-to-remember host names.

It's called the Domain Name System, commonly known as DNS. Your Internet service provider (ISP) provides you with the service, generally giving you addresses to two DNS servers as part of your account setup.

There's a great alternative, however, to the DNS your ISP provides. It's called OpenDNS. It's free, and it's loaded with extra features.

One of them is the ability to filter objectionable content. The How-to Geek offers a tutorial on exactly how this can be done. Just click here.

Facebook Woes

Q: So over the last few days, friends have been "writing" spam things on my wall such as "Hey, check out these local hotties, it's a good site to browse =) http://gracieledozux.blogspot.com so many to chose from!"

I have ignored the messages and deleted them. When I question the friends who sent them, they say their Facebook pages have a virus.

Today Facebook sent me a message saying I had to change my password. This seemed like it might be classic phishing, but when I went to the main site, it would not let me in and said my password was invalid. When I e-mailed privacy@facebook.com, as the pop-up message advised, the e-mail just bounced back to me.

So I went to the main Facebook page and reset my password there. Everything now seems to be fine.

My question: Have you heard of this before and what does it mean? Has Facebook been hacked and taken over, or just my friends' profiles?

A: Facebook is just fine, and thanks for asking.

I agree with you that this is probably a case of "phishing," which, according to the Wikipedia entry, is defined as "the criminally fraudulent process of attempting to acquire sensitive information such as usernames, passwords and credit card details by masquerading as a trustworthy entity in an electronic communication."

One way this might have happened is by you or one of your friends receiving an e-mail which appeared to come from Facebook.

"Please log into your account," it might have read. "Just click on this link."

The link, of course, takes you to a site which looks just like the Facebook login page, but is in reality a page designed to capture your username and password.

You put in your username and password. The phishing site records it and then gives you an error message about the password not being right (or some such). Then it sends you to the real Facebook site for a genuine login.

But now that the phisher or phishing "bot" has your username and password, he or it can write on your "wall" or the "walls" of any of your friends — just as if it was you doing the writing.

When you and your friends change passwords, the problem goes away — until the next time one of you gets that fake e-mail and the process starts all over again.

Just be thankful it wasn't your bank-account information!

The safest way to avoid this is to not to click on links in an e-mail, even one a friend sends you. If the phishing filter feature is turned on in your browser (make sure the browser's up-to-date), it should warn you before this happens.

Also, get into the habit of checking the actual Web address when you get a suspicious-looking e-mail. A secure Web page will have these three elements:

— The domain name is correct ("images.facebook.com" has "facebook.com" in it, whereas "facebook.WeWantToRipYouOff.com" does not).

— If the Web page is asking for sensitive information, it should be secure — the address in the "Go To" address box will be proceeded by the letters "https" as opposed to "http". The extra "s" means "secure".

— There should be a little gold "lock" symbol, which also means the page is secure. In Internet Explorer 7, the gold lock will be at the end of the Go To address box.

The Car Always Runs Great at the Garage!

Q: Last Monday night, we had a storm that shut the power off for three hours. When power came back, I turned on my desktop and the thing showed the pretty red Compaq logo for eight minutes.

I figured something happened — that the registry had to reset itself and all was well with the world. I installed a program, rebooted my machine — and again, it stalled for eight minutes on the pretty red Compaq logo.

After cleaning up the startup menu, checking boot.ini and checking the BIOS, it still sat on the annoying red logo for eight minutes (yes, the once-pretty logo has now become annoying).

I even unplugged the machine for a hour, but it still did this.

I still had warranty on it, so I took it in for a "warranty diagnosis," where they sat on it for four days and then declared there was nothing wrong with it.

I got it home last night, and they were right — nothing wrong! Any ideas?

A: It could be several things. The problem is that it is not displaying what is going on, so there is no way to really tell.

Since you seem to be familiar with the BIOS — the PC's Basic Input-Output System, which runs before the operating system loads — you might want to go in there and look for something about a fast start-up (disable it) or verbose start-up (enable it). It should be something along those lines, depending on the BIOS.

What you are trying to get it to do is show you the individual steps it takes as it runs the "Power On Self-Test" or "POST." It could be that it is running a memory test and having problems, or checking the hard drive for consistency, which sometimes can take a while.

Blind Men and an Elephant

There's an old story about a group of blind men and an elephant. Each of the blind men feels a different part of the elephant, and then disagrees with the others as to what the elephant is really like.

The one who feels the tail argues that an elephant is like a length of rope; the one who feels a leg argues that the elephant is like a pillar; the one who feels the tusk argues that the elephant is like a tree branch; and so on.

Q: In reading your "feedback" regarding the transition to digital television (DTV) there seems to be some confusion.

On Feb. 17th, 2009, television broadcasters will be shutting off their analog transmitters. Those who still receive television off-air will require a set-top box or a digital (ATSC) tuner in their television. Any TV set purchased after March 1, 2007 has to include a digital tuner.

As one of your responders noted, existing UHF antennae may be used for reception. A special "digital" antenna is not necessary.

This also has nothing to do with cable or satellite television. Cable offers both analog and digital transmission, and satellite is all-digital. The only mandate by the FCC on the cable companies is that they must offer analog signals as long as they have at least one analog channel in their line-upa through 2012.

A: You are absolutely correct — it is really about the tuner. And the elephant is like a length of rope.

But here's the whole elephant: One hundred and seventy-five days from now, there will be two groups of Americans — the ones who can still watch TV, and the ones who can't. Members of the latter would not likely know what a digital tuner was if it kissed 'em on the cheek and called 'em "Momma."

So here's the simple rule of thumb. If you're hooked up to satellite or have cable TV, you shouldn't have to worry. If you have a new TV (purchased after March 1, 2007) it will be OK, unless it came with a label that said it wouldn't be.

But if your TV is older, and you currently get your TV from an on-roof antenna or rabbit ears (as opposed to cable or satellite) then you will probably have to get a converter box — the sooner the better.

And that link, again, is www.dtv.gov.

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

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