I received a code with the 4th edition of Getting to Know ArcGIS for a 180 day trial version of ArcGIS. I have downloaded the software, but somehow accidentally selected "concurrent user" rather than "single user." I managed to change that using ArcGIS Administrator by following directions posted here. I ran the authorization wizard and it said it was successful, but then it reverted to concurrent user and ArcMap would not launch. I re-read the post and ran ArcGIS Administrator as admin and now it is staying with "single user." However, now when I run the authorization wizard with the same code from the email, it says "authoization failed." What do I do now?