Haven't had a single problem using this program to access my WinXP Pro. PC from my Mac w/OS X 10.1.x or later since this software was initially released. Granted, my Mac-to-PC connection is at home and simply over my LAN, so that's probably helped. But I've also had little to no problems using the Windows version of RDC to access my PC at home from my PC at work (w/ Win2K).