I have a problem sometimes with gadgets malfunctioning and hogging CPU and memory resources. They don’t display properly anymore either until I restart the sidebar process.
Fortunately, this is a known problem, and according to Microsoft, symptoms include: “Gadgets may appear as black squares, may appear to have vertical green lines down the center or may not appear at all and may have a blue exclamation mark next to it, or calendar gadget may display without dates”
Microsoft has released two potential fixes for this problem:
Microsoft Fix it 50617 – “This package will change the registry value for Value data in the Zones subkey to 0 for you”
or if that doesn’t do the trick, follow it with:
Microsoft Fix it 50618 which is designed to delete the extra (parasite) zone from the Zones subkey