Blaming lateness on your satnav is right up there with 'the dog ate my homework' in lame excuses

Look, when I'm lost, I know I'm lost. Now could the machine please leave it out with the monotone gloating in a dull Received Pronunciation accent. I've already worked it out myself.

And while everyone's telling me I really should de-clutter my life, this tangle of cables in my car - from satnav to laptop and from there to otherwise long-forgotten cigarette lighter socket - really can't be doing me any good.

My passenger isn't impressed, either. She has a computer precariously balanced on her lap - and she's the one who has to make the call to say we're late.

Why should I have to stress over whether there are so many high buildings that they mess up the satellite signal? Because if the signal's lost then I'm in trouble, no matter how close to my windscreen I've managed to set up the satnav receiver.

It's even worse in the middle of nowhere. Some days I can't even coax a grudging acceptance of my target address. The postcode isn't enough: it has never heard of the road, apparently.

Or it is known. Except it's in Wigan. Which is not great when you're in Wolverhampton. I'm left wistfully remembering all those shouting matches with my map-wielding partner.

Perhaps I'm just too trusting. Do many other people actually listen to their GPS systems? When fellow drivers find themselves in a cul-de-sac and are advised to "turn right" - into a lock-up garage - surely they smell a rat.

OK, so I'm no Stirling Moss. But as a stressed woman knocking 40, I'm reportedly a target customer. Well, I can't take much more of this anxiety. Having spent 20 minutes setting up the system I feel duty-bound to see it through to the hopefully not-too-bitter end.

The worst came when my 11 o'clock appointment deteriorated into my 12.30 - all because of yet another mess-up with the satnav. The man I was meeting was fuming. And so was I.

Blaming it on your satnav must be up there with "the dog ate my homework" lamest excuses of all time. But it was true. I'd spent two hours on what should have been a 30-minute jaunt to the outskirts of Stoke-on-Trent. I'd driven round the city centre three times before sitting in traffic on the notorious A500 and crossing the border into Shropshire.

There was a simple explanation, it transpired. Just 24 hours earlier I'd lent my system to a friend's husband to go to the other side of Shrewsbury. On programming my route the following day, it refused to register that I'd pressed that most vital button, "set as destination".

There was nothing for it. On the way back I bought an A-Z.