For users who currently have a previous version of ArcGIS License Manager and wish to migrate to the latest 10.6 version of ArcGIS License Manager, follow the instructions below:
10.0 to 10.5.1 License Managers
If you are currently using ArcGIS 10.0 License Manager through ArcGIS 10.5.1 License Manager, please view details under the topic License Manager Installation and Startup. If a Portal for ArcGIS instance will be configured to use ArcGIS License Manager, please also review information in the ArcGIS License Manager for ArcGIS for Portal Useful Information and Best Practices topic.
9.x License Manager
If you are currently using a 9.x License Manager, you first need to uninstall this older version to proceed with the installation of ArcGIS 10.6 License Manager. License files at version 9 or earlier will not work with the 10.x versions of the License Manager. You will need to first authorize licenses on the license server using the new authorization information sent via email by Esri Customer Service before starting the license service.
Contacting Esri Customer Service
If for any reason you are unable to locate your authorization information, you can contact Esri Customer Service and request that it be resent.
In the United States, you can contact Esri Customer Service by calling 888-377-4575 or visit the Esri Customer Service site.
Outside the United States, contact your local Esri distributor.