There Was An Error Parsing WS-Trust Response From The Endpoint. This May Occur If There Is An Issue With The ADFS Configuration [Microsoft Office 365]

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How to fix "There was an error parsing WS-Trust response from the endpoint"?

Issue Description: When using Integrated Windows Authentication (IWA) from Office 365 Scope, the following error is thrown when trying to authenticate

Full Error In Text:

Message: An error occurred sending the request.

 ---> RemoteException wrapping Microsoft.Identity.Client.MsalClientException: There was an error parsing WS-Trust response from the endpoint. This may occur if there is an issue with your ADFS configuration. See https://aka.ms/msal-net-iwa-troubleshooting for more details.

Root Cause: This can happen due to the following reasons

1. Azure App Registration has Public Client Flow Disabled
2. Other Federation service than Active Directory Federation Services (ADFS) is being used
3. ADFS is only partially configured

Resolution:

1. Azure App Registration has Public Client Flow Disabled

Go to Azure -> App Registrations -> -> Go to the Authentication blade -> Enable "Allow public client flow" under Advanced Settings Other Federation service than Active Directory Federation Services (ADFS) is being used Integrated Windows Authentication (IWA) is only working with Active Directory Federation Services (ADFS). Other federation services, such as OKTA, Push Federation, OneLogin, PingOne are not supported by IWA. Read more about IWA on Using MSAL.NET with Integrated Windows Authentication (IWA) ADFS is only partially configured IWA will leverage your organization's existing ADFS configuration. In order to work SSO must already be implemented with Entra ID (formerly known as Azure AD). Also, the Robot user must be added in Entra ID as a Federated User. If the above are in place, but IWA still does not work, reach out to the organization's infrastructure team to further investigate this. Read more on How to set-up ADFS for Microsoft 365 for Single Sign-on ? .