Is there a solution I'm missing? Or perhaps a root cause I haven't considered?
Switch to IE 8.
Sorry, I just couldn't help myself.
Thou art a blasphemer!!!
jk, but seriously, I refuse to use IE. I hear it's better then it used to be, but I guess I'm just stubborn.
Re-install it, that usually fixes everything.
If it is spyware, I suggest getting rid of norton.
Or atleast get spybot.
Sorry, norton is another program I don't like.