NAV 2010 file scan issue

Updated NAV 2010 to Ver. 17.5.0.127 on Win 7 machine.  Quick scan and Full scan now do not actually scan any files but sit acting as if they are doing something.  Scan has been running for over 2 hours with no change.  Stopping scan has no effect.  Program must be terminated from Task Manager.  Uninstalled and reinstalled NAV with same results. Any ideas?