Additional Details
Typically when a Renos' executable file is run, it drops a DLL file into Windows System folder and registers it as a system component. The DLL is the main Renos component. It shows a blinking icon in System Tray and periodically (actually quite often to be annoying) shows a fake security warning:

When a user clicks on this alert, his web browser is redirected to a website that offers a cleaning utility (usually anti-adware) for download.
Renos executable file is usually dropped from certain websites that a computer user browses.