Windows Update Does Not Recognize Administrator

Vista SP1. I just completed many updates from the Windows update site. With
several non critical ones left, I went back to finish. Now I can't download
/ install because it says I need Administrator permission. I checked user
accounts and of course there is only one account listed and it being
administrator, which I'm logged in on. I tried changing the account and it
recognizes me as an administrator and allowed me to make changes.
Applications requiring administrator work just fine but the update site
does not As per an earlier post I read here, I ran Update Agent 3,
still no joy. How can I regain update site permission.

Thanks