I've tested this version on OS X 10.4.0. Both my gateway and LAN computers (PCs and Macs) have no problem at all accessing Internet via browser and email. I've tried a variety of web sites and this update appears rock solid. I've used various versions of IPNR and IPNRX for about 7 years. The best part about the product is that it's virtually invisible nearly all the time. It does its job well without getting in the way.