I am following the WSO2 Identity Server documentation to set up a sample scenario. However, when I try to log in to the interface, I am immediately prompted with an error message stating 'SAML 2.0-based single sign-on: Error processing the authentication request. Please try to login again.' This occurs even before I enter my username and password(alex or cameron). How can I resolve this issue?
This can happen when the initial authentication request that you are sending from the client is not valid. The most common reason for this is a signature validation error in the IdP. Can you check if the request/response signing is enabled in your service provider configurations and in the sample applications .properties file? As a first step to diagnose the issue, you can try switching off these request/response validation configurations and try. In the mean time, please share if there are any error logs in the console and in the tomcat server so we could narrow down the issue.