HydraVision has some problems when working in multi-user environments. It's probably trying to start it, while it's already running from the previous user's session.
If you do not need HydraVision, I advise you to run the AMD uninstaller and choose to uninstall HydraVision while keeping the other components.
If you do need it, try disabling HydraVision from running at the start-up and run it manually.