Skip Peterson / AP The hand set and computer control box of the Victory Strategies phone bank system is shown in Greenville, Ohio, Oct. 28, 2008. Up to ten phones can be used and all of the responses are recorded into the computer system, making it more efficient.

Related Robocall complaints up despite do-not-call list Associated Press

Rachel’s back, and this time, she’s brought her friends. Despite ongoing efforts by the Federal Trade Commission, complaints about robo-calls — from “Rachel from Card Services” and other automated telemarketer scammers — have skyrocketed from 65,000 monthly two years ago to 212,000 more recently, according to the Associated Press. What’s going on?

Blame technology, for one thing. “A lot of it has to do with the fact that the Internet is now connected to the phone system,” says Bikram Bandy, an attorney with the FTC. The tech tools scammers need to ply their trade have also gotten cheaper. “The people who are violating the telemarketing laws can get started with a very low capital investment cost.”

Increasingly, overseas scammers rely on inexpensive VoIP phone connections to run their robo-call operations out of reach of U.S. authorities. In addition, technology that lets a caller put fake information into the recipient’s Caller ID — a practice known as “spoofing” — has gotten cheaper and easier to use, making it harder for law enforcement to trace the calls back to their source.

(MORE: Feds Bust the Mother of All Robocalling Rings)

“The Caller ID is a very weak lead for us,” Bandy admits. Still, it’s worth filing a complaint with the FTC. Bandy says the number of gripes is one factor the agency considers when it targets a company to investigate. “We still get a significant volume of complaints about what we call the ‘Rachel cases,'” he says, referring to calls that offer services like credit card interest reductions, foreclosure help and debt elimination — all of which prey on on financially distressed people. “It is still a priority, what we call last dollar frauds.”

In some cases, the FTC has targeted “dialers,” the technological middlemen who route the calls, since one of them can serve several robo-calling operations.

If you’re wondering, “What about the do-not-call list?” the unfortunate reality is that most of these robo-callers just ignore it entirely. After all, marketing robo-calls are illegal unless you’ve specifically given a company permission to contact you that way, so what’s one more violation? “Fewer telemarketers are checking the FTC list to see which numbers are off limits,” the AP story states. “In 2007, more than 65,000 telemarketers checked the list. Last year, only about 34,000 did so.”

(MORE: 2.6 Billion Robo-Calls Later, Why Won’t Rachel from Cardholder Services Just Go Away?)

In fact, if you answer a robo-call, it’s unwise to bother following any prompts the recording might offer to be taken off their calling list. Not only will this not work, but the prompts are used as a trick by telemarketing operations to find out if there’s a live person on the other end of the line. When frustrated people inadvertently confirm that for them, the robo-callers can bundle up lists of just those numbers and resell them, Bandy says. “They monetize those live numbers.”

This is why the FTC recommends just hanging up on robo-calls, or not picking up the phone in the first place. The less contact, the better.

Although it can sometimes be hard to tell a “Rachel” from a legitimate call from a financial institution, there are a few red flags. If it’s “Rachel” or “Ann” on the other end of the line, the name that shows up on your Caller ID is almost always something generic. While there are legitimate companies out there with nondescript names, you might want to let your voicemail catch those calls; if it really was somebody trying to reach you, they’ll leave a message.

Another quirk common to many robo-calls is a seeming preference for certain area codes. Bandy says if the call is being disguised by what he calls “dead number” spoofing, “You tend to see a lot of them come from less populated states.” The spoofing program looks for a number that has already been created but isn’t being used, which means they often come from places with more assigned numbers than phones to take them, like North Dakota, Montana or Utah.

(MORE: Top Consumer Complaints: Our Latest, Biggest, Weirdest Grievances)

Treat the calls like a stranger knocking at your door. Don’t recognize the person? Weren’t expecting a visit? Don’t let them in. Again, if it was a legit call, they’ll leave a message. Some people look into call blocking, but Bandy advises against paying for this. It might not even be all that effective, given how many of these scams there are and how fast they can change.