Back here, I wrote about getting text spam from a company despite having put my phone number onto the Telephone Preference Service database.

Well, last night got home to find a letter from the Data Protection Commissioner, saying “We have spoken to this company, and they are certain that they never texted your mobile number. However they might have texted your second line if you have one. You might like to check.” (Slight paraphrase..)

Now, it so happened that the other day I received another text spam, so I called the company up and asked whether they were using the TPS database. Yes, said the bloke. Is my number on it? I asked. Tappity-tap: yes. So why have you texted me? We haven’t, he said.

Then he asked for a four-character code at the end of the text. I gave it; more tappity-tapping. “We sent that to..” And he named a mobile number completely unlike mine. “I’ll call it, shall I?” he said. And my phone starts ringing – with a “data call”.

Surprised? Both of us were. But at last a mystery was beginning to unravel. For ages I’ve been plagued by “data calls” from various numbers; when I call them back they deny all knowledge of calling my number. I’ve had people put traces on outgoing company exchanges (I can be very persuasive) to track whether my mobile was being called; and turned up nothing.

Now, it seemed there was an answer. Orange, my provider, must have allocated me a data line and not told me about it. And lo, when I called Orange and asked about this, they reeled off two numbers, one being my “fax” number and the other being my “data” number, which they’d never told me about, and which had never appeared on my bill or one my phone.

When did they create those numbers? “Oh.. 1995,” said the Orange operator. That is, when I joined (I’ve been an amazingly faithful customer, though they’ve never given me reason to complain). Back then, mobile networks imagined we’d want fax and data sent to our phone. Instead, that’s been overtaken by the Net. No need for those extra numbers.

So the moral is: if you’re plagued by mystery data calls, or unwanted text spam, calling your operator to check whether they have assigned you a couple of extra numbers might pay rich dividends. I’ve deleted them. The text spam has stopped. At least, for the moment…