We are aware that we need to always have a original cheque number for each customer. To this end when we use Visa we always use ...visamonthdayyear....to ensure that it is unique to that particular customer. Every once in a while when posting visa transactions to numerous customers using the same date for the various customers , one of the transactions will come up as a cash posting error saying that the number has been previously posted. When we check, that number has never been posted previously. When it happened today it was the first payment for this customer. It generally happens when the customer numbers are close in sequence. (We use four digit number for our customter codes). Have anyone else reported this problem?