Q: Some of us who are upgrading from Windows 7 to Windows 10 will need to buy a new PC. What are the advantages of buying a PC with a hard drive vs. one with an SSD (solid-state drive)?

Jon Belisle, Maplewood

A: An SSD is a computer chip-based storage device that can take the place of a hard drive in a PC. Whether you need one depends on how you use a PC and how much you want to spend. Here are some things to consider:

An SSD retrieves stored data faster than a hard drive, but not a lot faster. In one group of tests, an SSD started up a PC 17 to 30 seconds faster than a hard drive would.

An SSD has no moving parts to wear out, so it's expected to last about one-third longer than a comparably used hard drive that contains spinning disks. But the difference may not matter to you; both an SSD and a hard drive are rated for well over 1 million hours of use.

An SSD uses less than half as much power as a hard drive, which means a PC laptop battery will last longer (by some estimates, about 30 minutes longer).

An internal PC hard drive costs less than an SSD, and that's reflected in the price of a new computer. If bought separately from a PC, a 1 terabyte hard disk drive would cost about $50 and a 1 terabyte SSD would cost $90 to $115.

Q: About a year ago, I bought what was said to be lifetime PC security from a company I wasn't familiar with. Several months later, the company said I had bought only "external security," and for an additional charge I could purchase "internal security." I bought that, too. Recently, the company warned me that all my software drivers had been turned off, allowing 22 foreign countries to monitor my computer activity. The company said it was unable to repair the damage, but could, for a fairly exorbitant fee, provide "lifetime drivers activation and support" and a "Windows license and installation." Is all this legitimate?

David Simmons, Baton Rouge, La.

A: Unfortunately, it's a scam. There are no such things as internal and external PC security. And no one could "watch" your PC activity if your software drivers were "turned off" — your PC wouldn't work at all. In the future, ignore anyone who tries to sell computer services by phone or e-mail. In addition, run the free version of the Malwarebytes security program (see tinyurl.com/j32jr94) to make sure that no malicious software was installed on your PC.

Q: Two readers asked how they could retrieve photos that were stored online. Jill Bloodsworth of Rehoboth Beach, Del., wondered whether she could recover photos from the online Kodak Gallery that failed to transfer to Shutterfly.com when the Kodak site shut down in 2012. Ellis Jackson of Macedonia, Ohio, asked whether he could recover photos that disappeared from an online storage service after he missed a deadline for contacting it.

A: The answer, sadly, is that your pictures are lost. Because online photo-storing services come and go, you can't rely on them to keep your photos safe forever. Instead, store your important photos in two places — if one location is an online storage service, the other should be your home computer, a flash drive or an external hard drive.

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