How To Fix SAML2155 - Unknown user ID source: '&1'

SAML2155 - Overview

• Message type: E = Error

• Message class: SAML2 - SAML2 Nachrichten

• Message number: 155

• Message text: Unknown user ID source: '&1'

Self-Explanatory Message

Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.

To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.

Unfortunately, there isn't any extra information in this error notice.

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Smart SAP Assistant

• What is the cause and solution for SAP error message SAML2155 - Unknown user ID source: '&1' ?

  The SAP error message SAML2155, which states "Unknown user ID source: '&1'", typically occurs in the context of Single Sign-On (SSO) configurations using SAML (Security Assertion Markup Language). This error indicates that the system is unable to recognize the user ID source specified in the SAML assertion.
  
  Cause:
  
  Incorrect Configuration: The user ID source specified in the SAML assertion does not match any of the configured user ID sources in the SAP system.
  Missing User ID Source: The user ID source may not be defined in the SAP system's SAML configuration.
  Typographical Error: There may be a typo in the user ID source name in the SAML assertion or in the SAP configuration.
  Inconsistent Identity Provider (IdP) Settings: The IdP may be sending a user ID source that is not recognized by the SAP system.
  
  
  Solution:
  
  
  Check SAML Configuration:
  
  Go to the SAML configuration in the SAP system (transaction code SAML2).
  Verify that the user ID source specified in