There are at least 2 other postings on this issue. I am also experiencing this problem. I have found references back to about October 2004. I have been dealing with Canadian and US tech support. US support has been better. Canadian support suggested using Real Player instead of SS, however it does not seem to have HiMD support. The US support (which I am not suppose to use as I live in Canada) has refered me to the "next level" of support. As they put it they have no more troubleshooting items for me to try. SS 2.1 worked perfectly on my other PC (Xp Prof. SP10). I can't get 2.1 or 2.3 to work. Sony needs to hear from everyone with this problem so that they (or Microsoft) will come out with a fix. MZ-NH600D SonicStage 2.1 and 2.3 Windows XP Home, SP2 all updates Pentium 4 3.0, 1 GB of RAM, USB 2.0, Original system from Dell When problem occured I was running in a relatively clean environment, No Anitvirus running, no spyware programs, no firewalls, no utilities, disabled most items. No Codec packs installed.