NIS 2012: Live Scan Status not showing in Windows XP

I have recently upgraded from NIS 2011 to 2012. I have 2 machines, one XP and the other WIndows 7. On the Windows 7 machine the dynamic scan status shows OK during a virus scan (as both machines did using NIS2011). The XP machine does not show the status during a virus scan and I have to go to history to see if the scheduled scan has run. Both copies were installed the same and I can find no obvious differences in the configuration. Any ideas please?