Home > Credit Card Processing > Shift4 Credit Card Processing > Shift4 Installation
If this is a new install (you have never had Shift4) or your Shift4 install hasn't been updated in years, you MUST run this program for credit card number masking, MENUS4MK.
You must run this program to properly mask existing card numbers and prevent entry of unmasked card numbers in the future. It's run using Run Program By Name