[mrmontage]

I was in a grocery store last week and the woman in front of me tried to use her credit card. It was refused repeatedly. Here is the strange thing. The cashier grabbed a plastic shopping bag and wrapped the card in it. The cashier slid the card through again and it was accepted! I asked the cashier if that happens often and she said yes. My question is how was that possible? The strip is covered by plastic and the machine accepted the card whereas without the plastic it got refused! What is going on?

[sixpack]

mrmontage
This is old trick taught to them by a service tech, I did it myself many a times. First off this means that the read head in the card reader is dirty which can easily be cleaned with a felt card treated with alcohol. The plastic bag gives a small gap between the dirty read head and the mag strip allowing the card to be read, it's not the card thats dirty it the card reader. These cleaning cards are available to them but most of the times the people just trash them not knowing what they are for. It goes back to the old saying "Read the instructions, if all else fails follow the instructions"