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There's another thread about this here: https://social.technet.microsoft.com/Forums/en-US/77990b62-d97f-4648-815f-b021ddc07b5e/windows-update-for-windows-server-2003-will-not-load?forum=winservergen It looks like WindowsUpdate works, whereas Microsoft Update doesn't. According to this... https://support.microsoft.com/kb/901037 ... you can click on "Change Settings" on the Microsoft Update page to disable Microsoft Update and revert to Windows Update, but this option is unavailable and greyed out due to the site being broken!