Q I have an almost-new LCD television that suddenly doesn't turn on. I noticed the problem a couple of days after a lightning storm. I'm puzzled because I have the TV, refrigerator and microwave oven plugged into the same surge protector, which is several years old, and the refrigerator and microwave continue to work.

What can I do to troubleshoot the TV, which has been used less than a dozen hours? Also, I'm considering purchasing an LCD HDTV, and now I'm worried it could be damaged the same way. What should I do?

KATY O'SULLIVAN, DULUTH

A If your household suffered a lightning-related power surge, several components in your TV could be damaged. Only a TV technician can tell you what's wrong and if the set is worth repairing.

But it's more likely that your TV was harmed by an ordinary electric power surge because your old surge protector was worn out -- the protectors sustain some wear every time there's a surge. (It's not surprising other household appliances weren't affected; they're not as sensitive as TV components.)

If you replace your surge protector, choosing a $20 one rated for 1,000 joules (a unit of energy) should protect a new TV.

While the protectors can't block the surge from a rare direct lightning strike, they can block surges caused indirectly by lightning's magnetic field.

Damage from power surges usually is covered only by extended warranties. But if it turns out your TV failure isn't related to a surge, see if you have standard warranty coverage.

Q I recently ran some suggested updates from Microsoft on my computer. My laptop always had audio before, but the icon now says, "No audio output device is installed." How can I fix this?

MARY MCLEOD, ST. PAUL

A There have been several reports of this problem. One solution is to undo the updates by running the "system restore" feature, which returns your computer settings to the way they were on a previous calendar date. (In the future, when this problem has been solved by Microsoft, you'll probably be able to download a cumulative update for Windows that won't cause this problem.)

To run system restore, go to Start, click "Help and Support" type "system restore" in the search window and click the arrow. From the resulting list select "Run the system restore wizard." When the wizard program starts, select "restore my computer to an earlier time" and click "next." Choose a calendar date from before you installed the Microsoft updates; only dates in boldface can be selected.

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