How To Fix SNC016 - Invalid external ID type (&1) passed

SAP Error Message - Details

• Message type: E = Error

• Message class: SNC - Secure Network Communication, SNC

• Message number: 016

• Message text: Invalid external ID type (&1) passed

What causes this issue?

The external identification type &V1& transmitted by the external
server program is invalid.
Only type "1" (base64 coded X.509 certificate) is currently allowed.

System Response

The logon is refused.

How to fix this error?

If the external server program is an SAP product (Internet Transaction
Server (ITS), for example), contact your helpdesk.
With other products, contact the manufacturer of the
product.

Procedure for System Administrators

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message SNC016 - Invalid external ID type (&1) passed ?

  The SAP error message SNC016 indicates that an invalid external ID type has been passed to the Secure Network Communications (SNC) interface. This error typically arises when there is a mismatch or misconfiguration in the SNC settings, particularly regarding the external ID types used for authentication.
  Cause:
  
  Invalid External ID Type: The external ID type specified in the SNC configuration does not match any of the expected types. This could be due to a typo or an unsupported ID type being used.
  Configuration Issues: The SNC parameters in the SAP system may not be correctly set up, leading to the system not recognizing the external ID type.
  Version Mismatch: There may be a version mismatch between the SAP system and the SNC library being used, which could lead to unsupported ID types.
  SNC Library Issues: The SNC library (e.g., SAP Cryptographic Library) may not be properly installed or configured.
  
  Solution:
  
  Check External ID Type: Verify the external ID type being used in the SNC configuration. Ensure that it is one of the supported types (e.g., 'SNC', 'SNC_PSE', etc.).
  Review SNC Configuration: Go to transaction SNC0 in the SAP GUI and review the SNC settings. Ensure that all parameters are correctly configured.
  Update SNC Library: If there is a version mismatch, consider updating the SAP Cryptographic Library or the SNC library to the latest version compatible with your SAP system.
  Check SAP Notes: Look for any relevant SAP Notes that might address this specific error. SAP frequently updates its knowledge base with solutions for known issues.
  Consult Documentation: Review the official SAP documentation for SNC configuration to ensure that all steps have been followed correctly.
  Contact SAP Support: If the issue persists after checking the above points, consider reaching out to SAP support for further assistance.
  
  Related Information:
  
  SNC Configuration: Secure Network Communications (SNC) is a security layer that provides encryption and authentication for SAP systems. Proper configuration is crucial for secure communication.
  SAP Notes: Regularly check SAP Notes for updates or patches related to SNC and security configurations.
  SNC Parameters: Familiarize yourself with key SNC parameters such as snc/enable, snc/identity/as, and snc/identity/peer to ensure they are set correctly.
  
  By following these steps, you should be able to resolve the SNC016 error and ensure that your SAP system's SNC configuration is functioning correctly.