Urgent: Agents League Hackathon Login Issue - AADSTS50020

The error indicates that the Gmail-based account is not recognized as a guest or member in the Microsoft Entra tenant that hosts the Agents League Hackathon application. This is a standard AADSTS50020 scenario where the user account from the identity provider does not exist in the resource tenant.

Actionable steps for resolution:

1. Confirm the correct sign-in account
   • Ensure the same Gmail address that received the hackathon registration confirmation is used at the Microsoft sign-in prompt.
   • If there are multiple Microsoft accounts or sessions in the browser, an existing session might be using a different account than intended.
2. Clear conflicting sessions
   • Sign out of all Microsoft accounts in the browser.
   • Open a new InPrivate/Incognito window or a different browser.
   • Try accessing the hackathon portal again and explicitly choose the Gmail account used for registration.
   This aligns with the guidance to sign out and sign in again from a different or private browser session when users might be signed into the wrong tenant or account.
3. Verify that the correct endpoint is used (for app owners/support team)
   • If the hackathon portal is configured as a multitenant or “multitenant and personal accounts” app, its Authority/sign-in URL should be one of:
     • https://login.microsoftonline.com/organizations for multitenant organizational accounts
     • https://login.microsoftonline.com/common for multitenant + personal accounts
     • https://login.microsoftonline.com/consumers for personal accounts only
   • If the app instead uses a tenant-specific URL such as https://login.microsoftonline.com/<TenantIDOrName>, then external users (like a Gmail-based Microsoft account) must be added as guests in that tenant before they can sign in.
4. Ensure the account type is supported (for app owners/support team)
   • If the app registration is single-tenant, external users cannot sign in and will see AADSTS50020.
   • In that case, the app registration must be recreated with a supported signInAudience value such as:
     • AzureADandPersonalMicrosoftAccount
     • AzureADMultipleOrgs
     • PersonalMicrosoftAccount
5. Confirm the user is invited/assigned if required (for hackathon support/admins)
   • If the hackathon portal is backed by an enterprise application that requires user assignment, ensure the Gmail-based account is:
     • Invited as a guest user to the tenant, and
     • Explicitly assigned to the enterprise application (or added to a group that is assigned to the app).
6. Contact the hackathon/tenant administrator
   • If the above user-side steps (sign-out, private browser, correct account) do not resolve the issue, the hackathon support or tenant administrator must:
     • Check sign-in logs for AADSTS50020 entries for the Gmail address.
     • Confirm whether the Gmail account exists as a guest in the tenant.
     • Invite the Gmail account as a guest if it does not exist, and/or assign it to the application if user assignment is required.

These steps ensure that the Gmail-based Microsoft account is correctly recognized in the Microsoft tenant hosting the Agents League Hackathon portal and that the application is configured to accept that account type.

References:

• Error AADSTS50020 - User account from identity provider does not exist in tenant