Update Icon Reappears In Systray After Update

I am using a Dell, Windows XP Professional laptop computer. It has a non- wireless connection to the internet via my LAN.Last week, the yellow update "shield" icon appeared in my systray and I updated Windows - the update was completed. Since then, the update shield icon has appeared in my systray four times. I installed the update each time, but it seems to have been the same update each time ("KB 967715"). If it is the same update each time, which it seems to be, why would the update "shield" appear in my systray four times within a week and a half to install the same update