One of the main reasons I switched to EAV -- and recommend it in the Microsoft Answers forums -- is because it has a much lighter impact on computers. Or at least it did, until I installed version 5. I have NOD32 a/v ver. 126.96.36.199 installed on a Win XP Pro sp3 box. It is an old machine (Pentium 4 2.6 GHz with 2.0 GB RAM), but with EAV v. 4, it worked fine. I have no other active anti-malware applications running (other than the Windows firewall). Now at various times (I haven't figured out the pattern yet) egui.exe grabs 99% CPU and won't let go unless I manually stop the application. It does this with the UI not displayed, although "Eset NOD32 Antivirus" appears in the "Applications" tab of Task Manager. When I use Task Manager to "End Task" and then re-start EAV, egui.exe drops down to 0%. I initially thought that this might have something to do with Live Grid, so I turned that off, but the lock-up still happens. I was under the impression that the scanner itself was ekrn.exe. If that's correct, it's not stuck on doing a scan (and in any case, the icon animation isn't running). Why does egui.exe take up so much resources? Can I go back to version 4 until this behavior is corrected? If so, what's the procedure for re-installing version 4?