Issue

When logging in with SAML SSO, the login fails and the following error appears:

ERROR - Connector: 404 - file not found for file: SubmitLoginForm

Environment

SAML module (all versions)

Cause

The SAML20.Startup microflow is not correctly configured to the application's after-startup microflow. This microflow will initialize the custom request handler /SSO/, validate all IdP configurations, and prepare the configuration entities required during the configuration.

Solution / Workaround

To resolve this issue, ensure that the SAML20.Startup microflow is correctly configured (as part) of the application's after-startup microflow. Follow the steps below:

1. Open the Mendix application in Mendix Studio Pro.
2. Navigate to App Settings > Runtime tab.
3. Locate the After startup microflow setting.
4. Ensure that SAML20.Startup is included in the after-startup microflow.
5. Redeploy the application and verify that users can successfully log in via SAML SSO authentication.

Additional information

Mendix documentation: SAML Installation and Configuration