Question: Regarding the scams (808ne.ws/1120col), what about to the home phones? I get nothing but scam calls all day long, even though I signed up for that “do not call” list years ago. Does that work anymore?

Answer: Yes, the National Do Not Call Registry still exists. It was created to stop unwanted sales calls from real companies, by informing telemarketers what numbers not to call. If you’re still getting a lot of unwanted sales calls on your landline or cellphone, they probably are from scammers who are ignoring the registry. There are various methods to block some of those scam calls, which we’ll explain after a refresher on the Do Not Call Registry.

It’s free to add a personal landline or mobile phone to the registry. Go to donotcall.gov or call 888-382-1222 from the phone you want to register; you can register more than one number. You can also verify that your phone is already registered by checking that website or calling that number. And you can report unwanted calls at the website; report the number that appeared on your caller ID — even if you suspect it was fake — and any callback number you were given.

Your Do Not Call registration does not expire. The Federal Trade Commission says it removes only numbers that are disconnected or reassigned, or because the registrant asks that it be removed.

As mentioned, the registry doesn’t “block” calls; it prevents telemarketing calls from real companies that abide by its rules. Moreover, the restriction does not apply to political calls, charitable calls, debt collection calls, purely informational calls or surveys — as long as none of them include a sales pitch, the FTC explains.

Generally speaking, telemarketers who sell goods and services must download the registry and remove any number on it from their calling lists. The registry applies to personal cellphones and landlines but not to business numbers.

We’ve heard from readers who registered a landline phone years ago but never registered their cellphone; they should. Federal regulations prohibit telemarketers from using automated dialers to call mobile phones without permission. Most telemarketers use automated dialers.

Now, on to scammers and others who don’t abide by the registry: Consumers have more ways now to block robocalls, using technology or a device to keep them from getting through. Which technology or device to use depends on the type of phone, as the FTC explains on its website:

>> Mobile phone: Check with your phone carrier to see what call-blocking services it offers or recommends. Block unwanted calls by downloading a call-blocking app, which intercepts calls predicted to be illegal sales calls or outright scams. Some, but not all, of these filtering apps are free. Find a list of call-blocking apps at 808ne.ws/ctiarobo, which lists apps for Android, BlackBerry, iOS (Apple) or Windows devices.

>> Home phone that uses the internet (VoIP): If your phone service comes from a cable company, or you have a phone/internet/cable TV bundle, you probably have VoIP service, which stands for Voice Over Internet Protocol. Check with your carrier to see what call-filtering options it provides or recommends, whether for free or an additional fee.

>> Landline phone: Check with your carrier to see what service it offers. Install a call-blocking device that might use a blacklist to block unwanted calls or divert them to voice mail, or a whitelist to let through approved numbers. Some services are free while others charge a monthly fee.

For more information from specific phone-service providers about how to block calls, go to the Federal Communications Commission’s website, at 808ne.ws/ stoprobo.

Write to Kokua Line at Honolulu Star-Advertiser, 7 Waterfront Plaza, Suite 210, 500 Ala Moana Blvd., Honolulu 96813; call 529-4773; fax 529-4750; or email kokualine@staradvertiser.com.