Prevx, the best anti-malware system on the market in my books, yet it suffers one fatal flaw: It has a 50% chance of correctly starting up upon log in. Here's the checklist to show that I've done everything on my end: Yes: I've reinstalled. Yes: I'm up-to-date. Yes: I'm running Prevx on both my Windows 7 and Windows Vista x64 systems, which are both entirely different PCs yet have the exact same issue. Yes: The problem also occasionally occurred on my previous Windows XP x32 system. Yes: I run Prevx with Microsoft Security Essentials, formerly ESET Smart Security 4. Makes no differences. Yes: My system startup is optimized and uncluttered and there's no excuse for Prevx not to start. My system is clean and maintained. & Yes: The background Prevx process may still start but the GUI doesn't load, which is responsible for executing scans, therefore, without it, your system is less protected. No: I won't accept that "Prevx technicians can't reproduce this error." It happens CONSTANTLY.