The little yellow shield in my tray menu keeps telling me to update to Service Pack 3. I click "OK", and it begins. About 6/10 of the way through, an error pops up saying that it couldn't install, and I have to go about taking all of the partially installed things off. I've restarted my computer, then attemtped again, but to no avail. Why is this happening? Why can't I update my PC?

















