I had a CC this morning that would not swipe, just got "Card Read Error" every time. So I tried putting a plastic walmart bag over it, swiped it worked. I have used the same trick before, but does anyone have any idea why it works??
You were getting "Card Read Error" most likely because there are scratches on the surface of the black magnetic strip on your card.
When swiped, the scratches cause spikes in the reader which cause the checksum to fail... because the numbers won't add up right.
Wrapping the card in plastic increases the distance between the the surface of the card (where the scratches are) and the magnetic strip, which reduces the strength of the spikes and smooths out the spikes... making the card work.
Also, clear tape (scotch tape) should work the same way... and may be a bit more convenient than a big plastic bag.
After working in retail for years i can honestly say this trick works almost everytime. The reason your card wasnt reading to begin with is due to smears or your magnetic strip is deteriorating and smearing along thee strip everytime you use it - it usually means the card is just old and its time to replace it. You can use the plastic bag trick or put one piece of thin scotch tape on the magnetic strip though and the machine will read it because the bag and the tape help block out the smeared parts of the magnetic strip and help it read the original one better.
sweet :D. I knew the issue was because the magnetic strip was damaged but I couldn't figure out why the plastic helped :P. Makes perfect sense now.
also another trick i picked up is using receipt paper and folding it around the magnetic strip. it works it just you have to do it right.
No problem. :]