Bought a new souped up computer or upgraded your computer recently. Did you notice that hibernate no longer works on your computer?
That is what happened to my new DELL Precision Laptop. I get a mysterious error message: "Insufficient System Resources Exist to Complete the API." Long story short, if your computer has more than 1 GB memory, Microsoft KB909095 is here for the rescue. Install it, the problem goes away instantly. Does not seem to have any side effects.