The other day I received a call on my landline. I don't use my landline often and I rarely receive calls so it immediately stood out as unusual.

Me: Hi
... (pause while an automated dialler routes the call) ...
Caller: Hello, I'm calling from (large UK ISP), it's about your internet. We've been doing some work in your area and there is a problem with your equipment.

Firstly, I'm always on guard when someone calls me offering help like this. The caller had an Indian accent and the background noise was quite loud and sounded like a call centre in India.

There is nothing wrong with being Indian or working in a call centre. Many times I have called my bank or another company I am using and I found myself talking to someone in an Indian call centre, no problems whatsoever.

In this case, this guy called me and the call centre was loud. The call centres that my bank uses try hard to keep background noise down, but not this place.

Unfortunately most scam calls do seem to come from India. What is interesting is that he had actually given me two pieces of correct information: I am in fact a customer of the large UK ISP he mentioned and recently they did do some work in my area because they sent me several messages about it using their email address and used my name. Regardless, I keep my guard up until I am convinced they are who they say they are.

OK, I didn't want to confirm anything so I tried to give an ambiguous answer to move the conversation along.

Me: Oh, yeah
Caller: So we think your equipment is faulty and you are not getting the internet speeds you should be getting

Oh, that's interesting; I was going to ask him my name next, because he should know my name if he works for the ISP I use. But instead I asked him about the speed thing.

Me: What internet speeds should I be getting?
Caller: Er, what do you mean?
Me: You said I'm not getting the internet speeds I should get - what speeds should I be getting?
Caller: Er, it's XXX Mbps download and YYY Mbps upload

Wow, he had given me the correct numbers. Now he had given me three pieces of correct information. Could he be legitimate? I still had zero trust in him. I decided to run a quick speed check while he was talking,

Caller: Can you look at the light on your router and tell me what colour it is?

Oh, that sounded suspicious to me. I know that the lights on my router are not going to give him much information at all and certainly wouldn't help debug the situation. If I had been calling him for some tech support, it might be reasonable to go through the basic steps of making sure the router is plugged in and turned on, but he called me and said my internet was working, only "not as fast as it should".

Nevermind, my speed check had already finished and the results aligned with what I would expect from my package.

Me: I just ran a speed check and I'm getting ZZZ Mbps
Caller: You are lying. Why are you lying?

At this point I hung up.

No one from (large UK ISP) would tell a customer they are lying. I'm not going to waste time listening to someone being rude to me.

If he was genuinely from (large UK ISP) they would send me an email or letter. He only said my network connection was slow, not dead, so email should arrive fine. (Large UK ISP) has never called me, ever.

I feel very confident that I was correct and even if I am not, the company will simply contact me again as this is a problem for them too, right?

It might seem surprising given that this guy had all this correct information about me, but did he really? A good scammer would have an answer for everything.

1. He knew my ISP

Did he? I'm using one of the top 2 or 3 most popular ISPs in the UK. It could easily have been a guess. If I had said I'm with another company he could easily have replied that he never said I was with (large UK ISP) but he could have said his company was doing some maintenance and spotted a problem coming from my end, or (large UK ISP) is subcontracted to provide service in my area on behalf of the ISP I am using, or something else.

2. He knew what internet speeds my package gives me

Is that true? I'm probably on one of the more popular speed packages. I don't think there are a huge percentage of people using faster speeds than me. The most popular speed might even be lower than mine but who isn't going to try and help if they are told their internet speed should be faster?

3. He knew my ISP had done some work recently

Irrelevant. They probably do work on configuration and infrastructure all the time without telling people about it. If I had said "Oh, I didn't hear about any work" he could easily have countered that the company didn't think it would affect me so never informed me. Coincidence.

I realised, this is the kind of technique a psychic medium would use: giving just enough information that it can seem to be quite specific but is in fact general and modifying the script depending on my responses.

Some other points I would like to make:

In this case I wasn't taken in at all, but you can see how even someone like me who is technically literature can find some kind of truth in what this scammer was saying.

A good strategy might be to always say "I have another appointment right now, can you put that information in an email and send it to me, thanks, bye". A genuine caller from a company you are using would be able to send you an email with the information.

Stay safe out there.