IIS 10.0 Detailed Error – 401.2

Most likely causes:

• No authentication protocol (including anonymous) is selected in IIS.
• Only integrated authentication is enabled, and a client browser was used that does not support integrated authentication.
• Integrated authentication is enabled and the request was sent through a proxy that changed the authentication headers before they reach the Web server.
• The Web server is not configured for anonymous access and a required authorization header was not received.
• The “configuration/system.webServer/authorization” configuration section may be explicitly denying the user access.

Things you can try:

• Verify the authentication setting for the resource and then try requesting the resource using that authentication method.
• Verify that the client browser supports Integrated authentication.
• Verify that the request is not going through a proxy when Integrated authentication is used.
• Verify that the user is not explicitly denied access in the “configuration/system.webServer/authorization” configuration section.
• Create a tracing rule to track failed requests for this HTTP status code. For more information about creating a tracing rule for failed requests, click here.

Detailed Error Information:

More Information:

This error occurs when the WWW-Authenticate header sent to the Web server is not supported by the server configuration. Check the authentication method for the resource, and verify which authentication method the client used. The error occurs when the authentication methods are different. To determine which type of authentication the client is using, check the authentication settings for the client.

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