Hmm from what you say.. I take it you didn't download and install the service pack yourself? If you did then you would have 'Evaluation Copy' on the desktop (usually visible in the bottom right-hand corner, you can also check by opening the control panel and clicking 'See the name of this computer'.. If it's installed you'll see Service pack 1 written). Also it's not an automatic download so you have to download and install it yourself. (unless someone else uses your machine and installed the RTM version?)
So if you haven't got service pack installed I'm going to need some more information...
What spec are you running and please as much detail as possible.
When the updates fail is there a error message and number?

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