How To Fix 1S540 - Certificate response does not match PSE

SAP Error Message - Details

• Message type: E = Error

• Message class: 1S - Messages for SSF ("Secure Store & Forward")

• Message number: 540

• Message text: Certificate response does not match PSE

What causes this issue?

The public key of the certificate response does not match the PSE. There
are two possible reasons for this happening. Either you created the
certificate request from another PSE. Or you have regenerated the PSE
after creating the certificate request (in Trust Manager: choose
Generate PSE or Replace PSE). Even if you regenerate a PSE with the same
subject name, you generate new cryptographic keys, that is a certificate
response that would match the old PSE does not match the new PSE.

System Response

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

How to fix this error?

Select the correct PSE to import the certificate response. If you have
regenerated the PSE after generating the certificate request, you need
to generate a new certificate request, and therefore request a new
certificate from the CA.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message 1S540 - Certificate response does not match PSE ?

  The SAP error message 1S540: Certificate response does not match PSE typically occurs in the context of Secure Network Communications (SNC) when there is a mismatch between the certificate presented by the server and the Personal Security Environment (PSE) configured in the SAP system. This can happen during secure communications, such as when establishing a connection to an external system or service.
  Causes:
  
  Mismatched Certificates: The certificate presented by the server does not match the expected certificate in the PSE.
  Expired Certificates: The certificate in the PSE may have expired or been revoked.
  Incorrect PSE Configuration: The PSE may not be correctly configured or may not contain the necessary certificates.
  Network Issues: There may be network issues that prevent the proper exchange of certificates.
  Changes in the Certificate Authority (CA): If the CA that issued the certificates has changed or if the root certificate is not trusted, this error can occur.
  
  Solutions:
  
  Verify Certificates: Check the certificates in the PSE and ensure they match the certificates being presented by the server. You can use tools like STRUST in SAP to view and manage certificates.
  Update PSE: If the certificate has changed or been updated, you may need to import the new certificate into the PSE. This can be done using the transaction STRUST:
  
  Go to STRUST and select the appropriate PSE (e.g., SSL Client PSE).
  Import the new certificate or update the existing one.
  
  
  Check Expiration: Ensure that the certificates in the PSE have not expired. If they have, obtain new certificates and update the PSE.
  Trust Relationships: Ensure that the root CA certificate is trusted in the PSE. If necessary, import the root CA certificate.
  Network Configuration: Check for any network issues that may be affecting the connection. Ensure that firewalls or proxies are not interfering with the certificate exchange.
  Review Logs: Check the SAP system logs for any additional error messages or information that may provide more context about the issue.
  
  Related Information:
  
  Transaction Codes:
  
  STRUST: Manage SSL certificates and PSEs.
  STRUSTSSO2: Manage SSO certificates.
  
  
  Documentation: Refer to SAP Help documentation for detailed steps on managing PSEs and certificates.
  SAP Notes: Check for any relevant SAP Notes that may address specific issues related to this error message.
  
  If the problem persists after trying the above solutions, consider reaching out to SAP support for further assistance.