Guys, The instructions in this link solved it for me ........ my problems were all based on running XP SP3 and this workaround works great! Make sure you put the SP2 Sernum file in the two places, re-install RSLinx and re-boot.... Then load the 1747 PIC/AIC driver and life will be wonderful! http://www.plctalk.net/qanda/showpost.php?...amp;postcount=9