Use not able to login using common endpoint in azure application

Question

User not able to login in common endpoint using azure application.

Steps To Reporduce :

1. Share file from SHarePoint to external user.
2. Try to login external user using Azure application link.

Answer 1

When you're using the Azure AD common endpoint, there are certain requirements and considerations to keep in mind, especially when dealing with external users (users from other Azure AD tenants or personal Microsoft accounts). Here are a few things you can check and try:

• App Registration Settings: Check the settings of your Azure application in the Azure portal. Navigate to Azure Active Directory > App Registrations > Select your application. In the "Authentication" section, make sure that the "Supported account types" setting is set to "Accounts in any organizational directory and personal Microsoft accounts" if you want to allow external users to sign in.
• User Type: Be aware that if the user is from another Azure AD tenant, they need to be invited to your Azure AD tenant as a guest user before they can authenticate with your application. You can do this from the Azure portal: Azure Active Directory > Users > New guest user.
• Consent: If you're using OAuth2 or OpenID Connect, the first time an external user tries to sign in to your application, they will be asked to consent to the permissions requested by your application. Make sure that this consent process is working correctly and that the external user has consented to the permissions.
• Error Messages: If the user is seeing an error message when trying to sign in, this can give you clues about what might be going wrong.
• Logs: You can check the Azure AD sign-in logs in the Azure portal for more information about why the sign-in attempt might be failing. Go to Azure Active Directory > Monitoring > Sign-ins and filter for the user's sign-in attempts.