I am a student trying to download ArcGIS on my laptop, I got it to download but during the installation wizard I chose the wrong setting, I chose advance concurrent use instead of advanced single use and I did not set a license manager which I need to open ArcMap. Can I change this or do I need to redownload the whole thing?
The disabled options in the Administrator usually mean that you don't have Administrator rights on your computer. changing licensing requires the app to change or add values in the HKLM registry area.
Reboot your machine and open ArcGIS Administrator. Check if you are able to change the license type.
Usually, I don't need admin. rights to change the license type in ArcGIS Administrator. It is disabled when I have any ArcGIS Desktop application open on my machine/ Task Manager.