Q: How long should a backup drive be expected to last? Mine is four years old. I haven’t had any problems, but I would hate to lose all my good work.

Barbara Aslakson, ST. Louis Park

 

A: How long a backup drive will last depends on whether it’s a hard drive or a flash drive, and how much you use it.

Hard drive failure is caused by wear and tear on its mechanical moving parts. In general, hard drives that are used regularly tend to fail in three to five years. (Most external hard drives sold to consumers have two- or three-year warranties. See tinyurl.com/3vfsxu6.) But a backup drive that is used once every two weeks might last much longer.

Signs of an impending hard drive failure include clicking or grinding noises. If you hear them, shut down the computer right away to minimize data loss.

Flash drives, which don’t have moving parts, can wear out as a result of the flow of electricity through them, reportedly after 100,000 writing or erasing actions. Some experts believe this can take more than 20 years of regular use. Flash drives can also lose their data by sitting idle for about 10 years, because the tiny electrical charges that represent data eventually dissipate. But don’t put too much stock in those long lifetimes. Remember that lower-capacity flash drives are inexpensive devices, and they are not immune to manufacturing flaws.

Despite the reliability of backup drives, I always advise people to keep multiple copies of irreplaceable data, such as photographs. In addition to storing data on a backup drive, you may want to copy it to a second drive or to one of the free online storage services, such as Dropbox, Google Drive and Microsoft’s SkyDrive.

Also remember that you can effectively lose stored information unless you transfer it to newer storage media every few years. That way you protect yourself against future changes in data storage formats or computer connection ports (floppy disks and USB 1.0 ports already are history.)

 

Q: I tried to download the four free security programs listed in last week’s column to my iPad. But my Safari browser said that it cannot download them. So what should I use for security?

Pete Duelo, Golden Valley

 

A: It’s not Safari that won’t let you download the four security programs. It’s the iPad and its iOS operating system, which are incompatible with the Windows PC security programs I wrote about. If you were using Safari on a Windows PC, you would be allowed to download the security programs.

But don’t worry. So far, the Bizcoaching virus I wrote about is aimed at Windows PCs and won’t harm your iPad. Your biggest security risk is losing the iPad and all its data. For tips on securing your iPad from prying eyes, see tinyurl.com/mvgk6ub.

 

E-mail tech questions to steve.j.alexander@ gmail.com or write to Tech Q&A, 425 ­Portland Av. S., ­Minneapolis, MN 55488. Include name, city and telephone number.