SONAR Component Error

I have Symantec Endpoint Protection installed on my window XP.  I got this error msg "SONAR Component has encountered a problem and needs to close.  We are sorry for the inconvenience" while I was running a Full system scan.  After the error msg above, my Symantec Proactive Threat Protection now says " Proactive Threat Protection Malfunctioning".  when i open Symantec Endpoint, under the Proactive Threat Protection, instead of "ON", it says "WARNING" and in the definitions, there is not date, it says "Waiting for updates". 

 

I have liveupdate set to automatically, but i went ahead and run it any again.  it didn't do anything.  I thought maybe my Symantec got corrupted, so i uninstall and re-install; after it scanned for a while, the same error msg appear again.

 

can someone tell me what is wrong?  Is it a MS OS thing or a Symantec?

 

thanks