There's a lot of things that can happen...I occasionally try to withdraw cash from an ATM in a busy area that is invariably*out* of cash. They don't give you a message that says "this ATM is out of cash. Sucks for you"--they give you something like "Your transaction cannot be processed at ths time" or similar. Happens all of the time...haven't used my NT card today but withdrew from it yesterday with no problem...