Polarbert...not sure whether you have found the solution for your problem. I had the same problem. I got this message saying sonic stage 3.1 installation failed all the time when I tried to install sonicstage 3.1. I have windows XP SP1 . I have some problem updating to SP2. So I downloaded microsoft windows installer 3.1 (KB893803) - which is available here. After installing that I was able to install sonicstage 3.1 . I first got this message saying it failed , when I tried again it installed successfully. Hope it helps...