Q: When I bought a Samsung Galaxy S7 phone about a month ago, I wanted to set different text-message tones for the various people in my contacts list. By editing my contacts list, I assigned custom tones to different people. But when a text message arrives, I still hear the phone's default tone.

My son has been able to set up different text-message tones for people in his contacts list, and he has the same phone, messaging app and wireless service provider that I do.

A technician at a Verizon Wireless store couldn't figure out what's wrong with my phone. I've done everything I can except perform a factory reset on the phone. Any ideas?

Mark Nicholson, Wells, Minn.

A: You have correctly set up individualized text-notification tones by editing your contacts list, so there are only a couple of things left to check.

Make sure that the tones you are using for text messages are stored in the phone's "Notifications" folder. If they are stored in the "Ringtones" folder, the messaging app can't find them.

In addition, make sure that any text-messaging tones you have added to the phone are compatible with the Galaxy S7. For a list of audio file types the phone can and can't handle, see tinyurl.com/lr6jcvr.

If those things don't help, return to the phone to its original settings (for factory reset details, see tinyurl.com/lg2clx7). That will erase your phone's data, so back up your information first.

If the reset doesn't fix the problem, the cause may be a flaw in your phone's firmware, the underlying software (separate from the Android operating system) that determines what the device can do. Don't try to fix that yourself, because tampering with the firmware might invalidate the phone's warranty. Instead, return the phone as defective and get a new one.

Q: I'd like to know more about IronKey, a flash drive that is encrypted to protect against virus attacks and computer hacks. Should I buy such a drive to be safe, even though it costs more than nonencrypted flash drives?

Myran Booker, Baton Rouge, La.

A: IronKey is one of several brands of encrypted flash drives that provide protection for data if the flash drive is lost or stolen. Data stored on one of these flash drives is coded so that it's unreadable unless you have a password that's known only to you or an intended recipient of the flash drive.

But unless the flash drive contains top-secret information that you are going to carry or send to someone, encryption is an unnecessary expense. Here's why:

An encrypted flash drive won't protect your PC from being victimized by computer viruses or hackers. Only PC security software can do that. The encrypted flash drive only guarantees that you will have a copy of your original PC data if something goes wrong with your computer. But any flash drive could do that, whether it was encrypted or not, provided that you store the flash drive separately from the PC.

In addition, encryption is risky because it temporarily turns your data into unreadable gibberish. If you lose or forget your password, that gibberish can never be decoded.

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