How To Fix SNC021 - Logon with external ID only possible with SNC-secured connection

SNC021 - Overview

• Message type: E = Error

• Message class: SNC - Secure Network Communication, SNC

• Message number: 021

• Message text: Logon with external ID only possible with SNC-secured connection

Self-Explanatory Message

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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 SNC021 - Logon with external ID only possible with SNC-secured connection ?

  The SAP error message SNC021 indicates that a logon attempt using an external ID (such as an SNC name) is only possible when the connection is secured with Secure Network Communications (SNC). This error typically arises in environments where SNC is configured for secure communication, but the connection being used is not secured.
  
  Cause:
  
  Insecure Connection: The connection to the SAP system is not using SNC, which is required for logon with an external ID.
  
  Configuration Issues: The SNC settings in the SAP system or the client may not be properly configured.
  Network Issues: There may be network issues preventing the establishment of an SNC-secured connection.
  
  
  Solution:
  To resolve the SNC021 error, you can take the following steps:
  
  
  Ensure SNC is Enabled:
  
  Verify that SNC is enabled on both the SAP server and the client. Check the SNC parameters in the SAP profile (e.g., snc/enable should be set to 1).
  
  
  
  Use an SNC-Secured Connection:
  
  Make sure that the connection string