I have Bit Defender Total Internet Security 2009. I purchased 5 licenses, installed 3 of them on Windows XP Professional machines, and it works perfect. I installed the other two on Windows Vista Home Edition machines, now most of the time Bit Defender runs fine, but sometimes it won't open. If I try to click the icon in the tray, it does not open at all, I have to restart the computer for it to start working properly again. Sometimes it will say Bit Defender services is unavailable when I open it up. This happens on both machines, so I am assuming it has something to do with Windows Vista. As a side note one is a 32 Bit and the other is 64 Bit. If anyone has any kind of solution, that would be great!