INTRODUCTION
This article describes how to diagnose single sign-on (SSO) logon issues in a Microsoft cloud service such as Office 365, Microsoft Azure, or Microsoft Intune by using Microsoft Remote Connectivity Analyzer. It also contains information about causes of common SSO failures and lists links to resources for how to troubleshoot the issue.
Remote Connectivity Analyzer is a free connectivity test platform for the cloud-based service. It tests the availability of the required federation service endpoint for expected behavior by acting on those services from the Internet.
Remote Connectivity Analyzer is a free connectivity test platform for the cloud-based service. It tests the availability of the required federation service endpoint for expected behavior by acting on those services from the Internet.
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The data flow of any SSO communication is predictable. The expected data flow pattern can be compared to or contrasted with a capture of the actual data flow that occurs during a failing SSO attempt to determine what might be wrong with the process.
How to run Remote Connectivity Analyzer to test SSO authentication
To run Remote Connectivity Analyzer to test SSO authentication, follow these steps:- Open a web browser, and then browse to https://www.testconnectivity.microsoft.com/?testid=SingleSignOn.
- Type your user ID and the password, click to select the security acknowledgement check box, type the verification code, and then click Perform Test.
Notes- Your user ID is your user principal name (UPN).
- You must enter the actual credentials that are associated with the SSO implementation that you're testing.

- If the connectivity test isn't completed successfully, expand the Test Details result tree by following the error icons to identify the first error that the test encountered. For any error state that's detected, expand the test result tree to the specific error, and then click Tell me more about this issue and how to resolve.
The following table lists causes of common SSO failures and resources that you can use to help resolve the issue.Test Common cause and failure sources Description Possible resolutions Attempting to retrieve domain registration and to validate federation status information for user
Analyzing the domain registration received for userAn error was found in the domain registration. This indicates that the domain that's used as the user's UPN suffix hasn't been federated. Federate the UPN suffix domain. For more information about how to do this, go to the following Microsoft website:
Troubleshoot domain federation and user account problems. For more information, see the following Microsoft Knowledge Base article:2530590 Troubleshoot account issues for federated users in Office 365, Azure, or IntuneUpdate the user's UPN to use the correct federated domain suffix. For more information, see the following Microsoft Knowledge Base article:2392130 Troubleshoot user name issues that occur for federated users when they sign in to Office 365, Azure, or IntuneAttempting to resolve the host name fed.contoso.com in DNS The host name couldn't be resolved. Public DNS resolution of AD FS service endpoint is failing. For more information about how to troubleshoot this issue, see the following Microsoft Knowledge Base article: 2530569 Troubleshoot single sign-on setup issues in Office 365, Intune, or AzureFor more information about the limitations of not exposing AD FS, see the following Microsoft Knowledge Base article:2510193 Supported scenarios for using AD FS to set up single sign-on in Office 365, Azure, or IntuneTesting TCP port 443 on host sts.contoso.com to make sure that it is listening and opened The specified port is blocked, not listening, or not producing the expected response. One or more of the services on which AD FS response relies stopped, were stopped, or are unavailable in some way. Restart the services. For more information, see the following Microsoft Knowledge Base article: 2419389 Internet browser can't display the AD FS webpage when a federated user tries to sign in to Office 365, Azure, or IntuneInvestigate a possible AD FS memory leak. For more information, see the following Microsoft Knowledge Base article:2254265 The "500" error code is returned when you send an HTTP SOAP request to the "/adfs/services/trust/mex" endpoint on a computer that is running Windows Server 2008 R2 or Windows Server 2008Investigate firewall-published AD FS service problems. For more information, see the following Microsoft Knowledge Base articles:2535789 Non-browser clients can't sign in after you set up AD FS in a "firewall-published" configuration2712961 How to troubleshoot AD FS endpoint connection issues when users sign in to Office 365, Intune, or AzureRetrieving AD FS metadata information from metadata exchange URL:
https://fed.contoso.com/adfs/services/trust/mexExRCA couldn't retrieve AD FS metadata. One or more of the services on which AD FS response relies stopped, was stopped, or is unavailable in some way. Restart the services. For more information, see the following Microsoft Knowledge Base article: 2419389 Internet browser can't display the AD FS webpage when a federated user tries to sign in to Office 365, Azure, or Intune
Investigate problems with the AD FS proxy server. For more information, see the following Microsoft Knowledge Base article:2712961 How to troubleshoot AD FS endpoint connection issues when users sign in to Office 365, Intune, or AzureInvestigate a possible AD FS memory leak. For more information, see the following Microsoft Knowledge Base article:2254265 The "500" error code is returned when you send an HTTP SOAP request to the "/adfs/services/trust/mex" endpoint on a computer that is running Windows Server 2008 R2 or Windows Server 2008Investigate firewall-published AD FS service problems. For more information, see the following Microsoft Knowledge Base article:2535789 Non-browser clients can't sign in after you set up AD FS in a "firewall-published" configurationValidating the certificate name Certificate name validation failed. Problems with the SSL certificate are limiting AD FS authentication. Troubleshoot the problems by using SSL certificate. For more information, see the following Microsoft Knowledge Base article: 2523494 You receive a certificate warning from AD FS when you try to sign in to Office 365, Azure, or IntuneCertificate Trust is being verified.
Certificate trust validation failed.Problems with the SSL certificate are limiting AD FS authentication. Troubleshoot the problems by using SSL certificate. For more information, see the following Microsoft Knowledge Base article: 2523494 You receive a certificate warning from AD FS when you try to sign in to Office 365, Azure, or IntuneExRCA is attempting to authenticate to the security token service at https://sts.contoso.com/adfs/services/trust/2005/usernamemixed A SOAP fault response was received from the Security Token service.
A web exception occurred because an HTTP 503 - Service Unavailable response was received from Unknown.The authentication to AD FS endpoints by using the federation trust is malfunctioning. Check and rebuild the federation trust. For more information, see the following Microsoft Knowledge Base article: 2647020 "Sorry, but we're having trouble signing you in" and "80041317" or "80043431" error when a federated user tries to sign in to Office 365, Azure, or IntuneCheck and repair the token-signing certificate problems. For more information, see the following Microsoft Knowledge Base article:2713898 "There was a problem accessing the site" error from AD FS when a federated user signs in to Office 365, Azure, or Intune
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