symefa.sys on windows XP

Hi

 

The other day when i left the computer and came back it had shut itself down, still on but looked like it shut down and didnt restart, i thought nothing of it at the time as the screen was blank no Blue Screen.

 

but when i tried to shutdown the computer today it had:-

 

Symefa.sys Page_Fault_in_nonpaged_area on a blue screen

 

I read this is Symantec related.

 

What caused this all of a sudden? and hows it prevented.

 

I havent changed nothing in my computer.

 

I use Windows XP Home

Nortons 2010

Version 17.7.0.12

says theres no new version when i check.

 

any help would be great to prevent it happening again.

 

thanks

 

Shirl