The full system scan will run for hours at 99% CPU usage without completing a scan.  I have left the scan running for 100+ hours, the furthest the scan will make it is about halfway.  The system has a 256gb drive, I have stopped Time machine and rebooted the system before running the scan.  Webroot has a message saying that a threat was detected but has not found a threat while running the scan.  Webroot Endpoint Protection CE 21.3.