See more of the story

Q: I read about the hacker attack last October that used household electronics, such as security cameras, to bombard a website with messages, causing the site to crash. Is there any way that people can protect their electronic devices so that won't happen again?

Sue Frenzel, Minneapolis

A: Internet experts are still looking for a solution.

The October attack took advantage of a new way for hackers to launch attacks against websites: Without the knowledge of homeowners, the hackers took over about 100,000 internet-connected household electronic devices, such as digital video recorders (DVRs) and the digital cameras used in baby monitors and security cameras. Hackers used the gadgets to flood a website with information requests, causing the site to crash (a so-called "distributed denial-of-service" attack.)

In this case, the attack affected consumers because the website victim was New Hampshire-based Dyn, one of several internet companies that translate the "www" addresses that people type into their browsers into the numbers that are the real Web addresses. When the Dyn website was knocked offline, consumers in several parts of the U.S. were prevented from reaching websites that Dyn served, including Amazon, Netflix and Twitter.

In the past, hackers launched distributed denial- of-service attacks by taking over poorly protected computers. Those attacks could have been prevented, at least in theory, if all computers were adequately protected by security software. But for devices in the Internet of Things, there is no security software. As a result, some internet-connected DVRs, cameras and home monitoring systems are easy pickings for hackers.

Here's the problem for consumers who own these internet-connected devices: Because the units weren't designed to have much security, they can't be upgraded to make them safer. Even changing a device's internet password won't make it safe, because hackers can still compromise it in other ways, such as by using techniques called "Telnet" and "SSH" (Secure Shell), that allow someone to log in to a computer from a remote location.

As a result, consumers will probably have to discard many of these early "Internet of Things" gadgets and replace them with new ones designed to meet higher internet security standards.

The security enhancements could make these home devices more expensive in the future.

Q: I've discovered that digital photos stored on my PC from as long ago as 2005 are corrupted. Some won't open at all, and others are partly blanked out. This appears to have happened randomly to photos that I've taken with several different digital cameras. What can I do?

Kevin Leonard, Colorado Springs, Colo.

A: Randomly corrupted files are a classic sign of a failing PC hard drive (see tinyurl.com/anfddds.) To avoid losing more photos or other data, replace the PC's hard drive immediately.

While a computer shop can copy your intact photos and other data to a new hard drive, it can't repair lost or damaged photos that were improperly stored by a failing drive. That data is lost

E-mail tech questions to steve.j.alexander@gmail.com. Include name, city and telephone number.