I installed the trial version of Prevx 3, 126.96.36.199(?) on my Windows 7 Pro pc alongside NIS 2010. Also installed is Sandboxie, which co-exists nicely with NIS. But after installing Prevx I can't open FF 3.5.7 sandboxed. FF opens when I didn't sandbox it. Removed Prevx, ccleaned the system and opened FF in Sandboxie with no problem. I don't remember reading anything about this but it has dampened my enthusiasm for Prevx for now. I'll try again in a month or two. Thanks.