Q: What can I do about random audio advertisements that I've been receiving on my computer for several months? At first, I just pressed the mute button. But then I began to worry that my PC was infected with malicious software. So I ran security programs from Malwarebytes, Kaspersky Lab and Norton, but they didn't eliminate the ads. Has my PC been compromised in any way?

Sherry Lampman, St. Paul

A: I doubt it. Because you've tried security programs without success, I think your problem is not malicious software but an unorthodox advertising technique used by some of the websites you visit. The audio or video ads you hear are set to begin playing as soon as one of those Web pages loads in your browser.

While some might argue that this advertising strategy is no more invasive than a website print ad that pops up unannounced, I think audio and video ads that play automatically are less acceptable. While you can click out of a print ad, it's unclear to most people how to turn off an audio or video advertisement.

Why do some websites use this technique? Because some advertisers request it, in the belief more people will listen to an auto-play ad than will voluntarily click on the ad to hear it.

Fortunately, you can change your browser settings to stop audio and video advertising from playing automatically. To alter the settings in the Microsoft Internet Explorer, Google Chrome or Mozilla Firefox browsers, see tinyurl.com/l5vmbjp.

Q: I've used a Dell 926 printer with my Windows Vista 64-bit PC for three years. But after a recent Windows Vista update, I get the error message "communication not available" from the printer. I know the printer is working, because it still prints for my Windows 8.1 laptop and its scanner function works with both computers. I've tried unplugging the cables, disconnecting the power and restarting the PC and printer, but nothing works. What can I do?

Jim Carbonneau, Lakeland, Fla.

A: Your problem could be caused by the printer driver software you're using or by some other damage done by the Windows Vista update. Try downloading the 64-bit driver software for your printer at tinyurl.com/o2f97yc. If your existing driver is outdated or was damaged by the Vista update, this should fix the problem.

If that doesn't work, trying using System Restore to return your PC's settings to the way they were before the update. For details, see the explanation and video at tinyurl.com/2bdvvv. Use "Method One" and choose a restore date before the Vista update.

Note: System Restore will erase not only the Vista update, but any software you've installed since the date to which you restore the PC. Your data won't be affected.

You can prevent future Vista update problems by changing the updates from automatic to optional (see video at tinyurl.com/o8g5fq8.) Only install updates listed as critical.

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