I have IE9 with Vista and Norton 360.
Just recently IE has not always booted up, just hanging and difficult to close, but made it after several attempts.
Removed all add ons and could find nothing, because I trusted Norton Toolbar, stop laughing, and removed all BUT that.
Removing NT seems to now make IE work OK.
Any offers of what might be a solution, apart from not using IE and I thought i needed Nor ton TB with the nasties out there.