this has cut a lot of my nuisance calls telephone preference service https://www.citizensadvice.org.uk/consumer/phone-internet-downloads-or-tv/stop-getting-nuisance-calls-and-texts/

I used similar to a referee's whistle Paul - I screamed loud and clear and they hung up never to call again. But this was no genuine caller Roger, I had been plagued with calls night and day for weeks from this particular number which gave, falsely, a local exchange number which is what they do now. Police would not do anything - telephone services gave me the runaround. As I suffer with bi-polar I was getting increasing more ill and I just snapped one day and screamed - one long piercing scream. They never called again! Nowadays if you can prove these companies are causing distress, the authorities fine them and close them down as they have done recently with a company.

Yes its nice to give them the runaround too john

I usually get the better of them by asking, "Which computer do you mean?" (I have six, not including my smartphone and my iPad). Then I ask which operating system are they talking about. (I run windows 98, XP, 7 32 bit, 7 64 bit, 8, and also 10). Of course I insist upon them answering me because if they know so much about my problems, at least they will know that. They usually give up after that. John

lol I only use in exceptional circumstances and oddly enough they never call back!!!!. I never asked them to call me and would willingly and vigourously defend any legal challenge.

Do not use a referees whistle as stated in earlier comment as you could leave yourself open to prosecution for causing injury to the caller especially if it was a genuine call rather than a scam.

Scam phone calls are quite easily cured with a referees whistle. Blow as hard as you can and it may puncture the ear drum. Happy days

had similar to above with alleged service provider ( nearly got caught ) don't accept any calls from anyone ref your computer or a service they purport to provide