I am using windows vista, and have installed norton 360. It was working fine but since last few days, the explorer has a red bar which says browsing not safe- auto protect off. It gives instructions on turning it on but that is not working. What do I do?

Check out the following from Symantec:

Red X is displayed on PC Security in the Norton 360 program interface and clicking Details shows "Off" next to Auto-Protect

Hope this helps!