Roger that on wrong browser...ben thar dun dat.
Richard,
A file called Scanctrl.lic holds your key. During uninstall it remains in the ScanControl folder and is defined during installation of the upgrade. Should one delete the file after "uninstall" the new installation has no reference to the "key".
If in fact you did delete after uninstall then uninstall latest upgrade, open Recycle and restore the Scanctrl.lic file, then redo the new installation using the link in your email.
If you did not remove the file (or folder) then as Mike suggested, the file is likely corrupt. Copy and send it to Ken for review.