It is very difficult (actually almost impossible) to screw up the magnetic strip on a credit card by subjecting it to the magnetic fields or the electric fields normally encountered in everyday life…..including airports, stores, bars etc. Most problems are caused by minute scratches on the mag strip. Ditto for 3.5 inch computer disks, computer hard drives, magnetic tapes etc.

In March my AMEX card would not swipe. The clerks rubbed it on their shirts/blouses, their pants, snapped it with their fingers, rubbed it with a greasy thumb but all with little success. I finally called AMEX for a replacement card. They sent out a new one via snail mail but WITH A BRAND NEW NUMBER. They said this is their policy.

MisterNice