I am trying to install Windows XP Mode from here: http://www.microsoft.com/windows/virtual-pc/download.aspx (the Hardware-Assisted Virtualization Detection Tool has given me the green for proceeding)
Even though my Windows has been activated a year or so ago, the download button leads me to a splash screen saying "Windows validation required". I am next forced to download a WindowsActivationUpdate.exe which, after downloading some mysterious "update", fails with the error message "Update installation failed, error information 0x80070002" (rough translation from German). I've tried running it both normally and as Administrator.
What could be the problem?