Re: "Old' and "solicitor" doesn't narrow things down...
1996, new (and first) PC with fax software and a voiceview modem sitting in home office.
Phone rings at too-damn-early on a Saturday and I get fax squeal when I pick up. And again. And again.
So I go downstairs boot PC and make tea while that happens. Then I start the fax software and out prints some poor woman's lab results with - as I'd hoped - a cover sheet with the phone number of the sender.
I call them, young woman answers and we fall down the rabbit hole:
"You are faxing the wrong number. Please check your machine."
"Impossible!"
"Okay. Let's review for a moment. You say you are faxing the right number. *I* say you are faxing the wrong one. What are the alternatives? Either I am right and you are sending - let me see - Mrs Elsie Zzzzzz's medical records to a private address, or you are right and I am a crank caller who has called you and accused you of sending a fax at exactly the same time as you actually did send a fax, and I have guessed randomly the exact details of the fax you are sending. You choose the more likely scenario."
"Okay. I'll re-check the number I dialed."
"Thank you. And I will shred the sensitive personal medical documents you sent to me, shall I?"
"Yes." Click.