SharePoint Online Add-In authentication Issue

Copper Contributor

I have registered a SharePoint Online Add-in using AppRegNew.aspx and I have given all the required permissions to it, I am using this Add-in in another software to access SharePoint Online resources, but I am getting authentication error.

1 Reply


Authentication issues with SharePoint Online Add-Ins can stem from various factors. Here are some common troubleshooting steps to help resolve authentication problems:

  1. Check App Permissions: Make sure that the registered Add-In (App) has been granted the necessary permissions in the SharePoint Online site collection where you are trying to use it. Permissions are set during the app registration process and can also be managed in the SharePoint site's App Permissions settings.
  2. Client ID and Secret: Ensure that you are using the correct Client ID and Client Secret values for your Add-In. These values are generated during the app registration process and are used for authentication. Double-check that there are no typos or errors in these values.
  3. Redirect URIs: Verify that the Redirect URIs in your app registration match the ones you are using in your application. Redirect URIs are crucial for the OAuth flow to work correctly.
  4. App Domain and Site URL: Ensure that the App Domain and Site URL in the app registration match the actual domain and SharePoint site where the Add-In is being used.
  5. App Permissions vs. User Permissions: Be aware of the distinction between the permissions granted to the Add-In and the permissions of the user trying to access resources. Sometimes authentication errors occur if the user does not have the required permissions.
  6. Token Expiry and Refresh: OAuth tokens used for authentication have a limited lifetime. Make sure your application handles token expiration and refresh properly to avoid authentication errors. Tokens can be refreshed using the refresh token obtained during the initial authentication.
  7. App Trust Settings: Check if the app trust settings are configured correctly in the SharePoint admin center. If the app's trust is not set up correctly, it can lead to authentication issues.
  8. Network and Firewall: Ensure that there are no network or firewall issues preventing communication between your application and SharePoint Online.
  9. Logging and Error Handling: Implement proper logging and error handling in your application to capture detailed error messages. This can help you identify the specific issue causing the authentication error.
  10. Microsoft Support: If you have exhausted troubleshooting on your end, consider reaching out to Microsoft Support. They can provide assistance in diagnosing and resolving complex authentication issues.

Please, remember that SharePoint Online and the technologies used for Add-In authentication can evolve, so it is important to consult the latest documentation and resources for accurate information on troubleshooting. The text and the steps are the result of various AI's put together.


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Hope this will help you.