Originally Posted by
empedocles
Under what conditions does this occur? If I am reading the OP correctly, he realized after he put the card in that it was not a cash dispenser, and then it wouldn't give the card back. Why would it not give the card back if the OP did noting wrong?
It depends on the machine and how it's configured. They probably could have configured it so that if you hit the clear button it would have given you back the card. They could have also configured it to assume that you were a thief trying somebody's card, and they configured it to capture the card to keep it from being tried in another machine.
The OP did something wrong, through they did not realize it. They tried to use a card in a machine they could not use the card in.
The easiest way to tell if it's a cash machine or not is to look for the plus or cirrus or visa or mastercard logos on it.