http://v4.windowsupdate.microsoft.com/troubleshoot/
When you try to install security\Critical Updates the installation fails and the
Windows
Update.log file contains error 80070643.
CODE wrote:
> I just installed win2k3 server std ed and started Windows Update - It
> finds 37 updates available - i select them and chose the "download
> and install". The download progress windows open but nothing happens
> in the progressbar for 30 sec - then it fills up in 1 sec and closes
> - it says - "No updates were installed".
>
> Why does it not download? Is there a port in the router that needs to
> be open?