An organization configures an ArcGIS Enterprise portal to allow single sign-on using Integrated Windows Authentication (IWA). Configuration includes…

When ArcGIS Enterprise is configured to use enterprise groups for membership, accounts for new users are automatically created in the portal during their first sign-in attempt. This process assigns a pre-configured default user type and role. If the organization has exhausted the number of available licenses for that specific default user type, the portal cannot complete the account creation. This failure manifests as an inability for the new employee to log in, as their portal account cannot be provisioned. Existing users are unaffected because their accounts and licenses have already been provisioned.

A. Their Active Directory accounts have not been added to the portal This is a symptom of the underlying issue, not the root cause. The accounts are failing to be added automatically upon login due to the provisioning failure.
C. Their Active Directory accounts have not had sufficient time to sync to the portal ArcGIS Enterprise does not use a background synchronization process for IWA. It queries the identity store in real-time, and account creation occurs on-demand at the first login.
D. The Web Adaptor cache must be cleared Clearing the Web Adaptor cache is a general troubleshooting step for site-wide configuration or connectivity issues, not for a specific user account provisioning problem based on licensing. ---

1. Esri, ArcGIS Enterprise Documentation. Portal for ArcGIS > Administrator > Manage your portal > Security > Configure enterprise logins. Under the "New member defaults" section, it states: "When a new member from an enterprise identity provider signs in to the portal for the first time, they are automatically added as a member and assigned the default role and user type configured for new members." This confirms the automatic provisioning process.

2. Esri, ArcGIS Enterprise Documentation. Portal for ArcGIS > Administrator > Manage your portal > Security > Troubleshoot accounts. In the section "I can't add a new enterprise member to the portal," the documentation explicitly states: "This may be because the portal does not have any available licenses of the user type that is configured as the default for new members." This directly identifies the cause described in the correct answer.

3. Esri, ArcGIS Enterprise Documentation. Portal for ArcGIS > Administrator > Manage your portal > Organization > Manage members > User types, roles, and privileges. This document details how user types are tied to licenses. The section "User types" explains: "Each member must be assigned a user type... The number and type of user types available in your organization are determined by your license." This establishes the link between user types and license availability, which is central to the problem.