3690953 - Error "Proxy error SOAP:1007 SRT: Unsupported xstream found: ("HTTP C: ode 401 : Unauthorized")" while submitting PEPPOL eDocuments

1. Any PEPPOL eDcoument(Belgium, Germany...) submission from transaction edoc_cockpit, returns error:
   "Proxy error SOAP:1007 SRT: Unsupported xstream found: ("HTTP C: ode 401  : Unauthorized")"
   
2. The SMICM log shows following error(refer 3187867 - How can I collect the ICM traces?):
   Bearer error="invalid_client", error_description="The client certificate is not configured in a service key of a Process Integration Runtime service instance. Client certificate:
3. User Provided SSL Client Certificate Authentication is used for integrating the business system with DRC Cloud Edition and to authenticate the business system.

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• SAP ERP
• SAP S/4HANA
• SAP S/4HANA Cloud Private Edition
• SAP Document and Reporting Compliance, Cloud Edition

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