@itman Have you checked your Event Viewer for any errors or warnings? You may see a Service failed to start with Windows, but was likely started on a subsequent attempt. NOTE: You may see some errors and warnings in Event Viewer, even if your computer is working fine. Also I noticed when uninstalling NVT OSArmor not all registry entries are removed. Older versions like 1.4.3 according to OSA dev have to be uninstalled before installing the newer 1.5+ versions. After that you can install automatically over-the-top of existing 1.5x versions or do everything manually.