What is wrong with people?
Not a week goes by, without someone moaning to me about the “unexpected item” error you get in self-service checkouts at the supermarket.
If you’re getting it, it is YOUR fault.

Seemingly it’s a problem we’re all having, all the time.
Well I’m not.
Ever.
I’ve never thought of myself as a genius, but as I’m seemingly the only person in the world who can figure out how to use these machines, I thought I’d write a post explaining this, why it occurs, and how to resolve it.

I’ve had no training in building these machines, but from what I can see, there’s two things going on.
1. You scan.
2. You put it in the “bagging area”.
First the machine scans a barcode, then it expects you to put something in the bagging area.
I’m pretty sure it checks the weight of the bagging area, to make sure you haven’t bought 12 toilet rolls, and scanned them through as a Snickers bar.

It will report “unexpected item” if you just chuck something in the bagging area, because you haven’t scanned it.
That’s your fault.

So scan it, then put it in the bagging area. Simple.
You’ve scanned it, it’s waiting for you to put it in the bagging area.

Where a few people get confused is where they use their own bags.
Given it measures the weight, you already know you can’t just put your bag in the bagging area.
You know this doesn’t work – don’t fight it.
Don’t blame the machine.
If you put a bag in the bagging area without scanning anything, it’ll complain. YOU are using the machine incorrectly.

If you’ve been struggling with this, the solution is so simple you will kick yourself.
For this example, I’ll be buying a 2pt bottle of milk.
You scan the milk, then put it in your own bag, then put the bag (now containing milk) in the bagging area.
It weighs it, and it is approximately the weight it was expecting.
You do this for each new bag, as you add them.
Simple.

If that doesn’t work for you, then you’re still doing something wrong. I haven’t had an argument with the machine about unexpected items in months.
The only argument I have is when you have 4-5 bags, you’re attempting to put money away and pick them up, and as you’re a tiny few seconds slower, it tells you “please take your items” as if you’ve forgotten.
I’ve got a simple solution to that too – swear at it. Profusely.