Problem: ArcGIS Pro is unable to verify licensing through the licensing portal
Attempts to log in to Portal for ArcGIS using ArcGIS Pro fails with the repeated prompting of the licensing portal login dialog window.
This issue is caused by an inaccurately defined portal configuration file (.json). This makes Portal for ArcGIS unable to identify the License Manager over the network despite using a valid URL to login.
In some environments, if the hostname in the portal configuration file (created in Step 19 of ArcGIS Help: Configure ArcGIS Pro licenses for your organization) is not defined in a fully qualified domain name (FQDN) recognizable by the license server, Portal for ArcGIS is unable to connect to the license manager to verify licensing.
If there are already licenses imported into the Portal site, remove these entitlements by clicking Remove Entitlements.
Click Import Entitlements > Choose File, and select the updated .json file with the FQDN of the licensing server. Click Import.
Verify the entitlements applied by clicking Get Entitlements.
Attempt to open ArcGIS Pro.
Remove old registry entries of ArcGIS Pro In some instances, the system registry contains information of older versions of ArcGIS Pro. Removing the registry entries allows the system to recognize the license changes made to ArcGIS Pro.
The instructions below include making changes to essential parts of your operating system. It is recommended that you backup your operating system and files, including the registry, before proceeding. Consult with a qualified computer systems professional, if necessary.
Esri cannot guarantee results from incorrect modifications while following these instructions; therefore, use caution and proceed at your own risk.
Click the Windows Start button > type regedit in the Windows search bar (open the Registry Editor).
Search for the following registry entries, and remove or rename them:
HKEY_CURRENT_USER\Software\ESRI\ArcGIS Online For Pro