Sometimes authorization of a new single use license for ArcGIS Desktop fails. The authentication wizard reports success, but when you look in Availability you still see the old expired licenses. This typically happens when you have had older licenses which
have expired on the machine.
The trick is to wipe the so called Trusted Store that ArcGIS Administrator is using.
Added Fri Mar 06 14:55:04 CET 2015 by Mats