Common guys I dont know how to explain you this. Ok I bought upgrade software from PAR to upgrade from PAR 6.52 TO PAR 6.6 so that I can use integrated credit card payment system in POS itself. After installing software, I have to enter following FEF code (03 03 A1 02 06 00 03 00 FF FF 34 5E 31 98 74) to activated payment function in POS menu. It is the same program for all stores except FEF code or key is different to activate in menu. My question is I saw FEF code for other store and the only difference between mine FEF code or key and other store is from (34 5E 31 98 74). The last five numbers are different. Is that store number or what? That's what I want to know. I dont want to keep buying software for each store but I have to do that cause PAR provides with FEF code. I was wondering if I can figure out last five numbers in FEF code by myself since first 10 numbers in FEF code is same for any store. Thank you