As any IT project manager will happily confirm, if you take an information system designed for one purpose and then wrap it up and try to use it for another, unrelated purpose, you will soon find out that life is not as simple as you had hoped. There will always be small, non-obvious exceptions to the rules that you blithely assumed would apply...

I was late for an appointment at The Dorchester - the posh hotel overlooking Hyde Park. It’s walking distance from my desk in Soho but Mayfair is a maze and time was tight, so I wanted to be reminded of exactly where on Park Lane it sits. I turned to the trusty Google Maps service. Which turns out not to be so trusty.

Searching for “the dorchester hotel” brings up two candidates: “A” being the famous Dorchester Hotel of Beverley Road, Hull, plus the other, evidently lesser-known Dorchester that I was after.

Clicking on “B” brought up a confirmatory picture of the correct façade, so I zoomed down to a suitable resolution to show the hotel’s locale.

And was a bit surprised to find myself looking at Rathbone Place, round the corner in Soho, rather than a prime piece of Mayfair.

I happen to know that the Google Maps arrow is actually pointing to a Royal Mail warehouse. This is probably because Google Maps gives The Dorchester’s postcode as W1A 2HJ. I think this actually functions as a sort of PO box. You’ll get the same result, incidentally, if you put IT Week’s published postcode of W1A 2HG into Google Maps. That postcode is used to divert bulky parcels away from our plate-glass entrance on Broadwick Street. The actual physical postcode for our office is W1F 8JB.

Similarly, The Dorchester’s actual postcode, helpfully retrieved from its customer-facing web site, is W1K 1QA.

I wonder how many people are being sent to Royal Mail outposts by putting too much faith in Google Maps and its flawed postcode system? The same error will of course be made by any digital map relying on postcodes - my TomTom GPS system makes the same mistake.

Forget the national ID card system, we need a proper national digital address system designed for people, not parcels.