3049516 - Error HTTP 403 or 401 When Sending Data from Cloud for Customer to SAP ERP/CRM/S4H via Cloud Platform Integration

• SAP Cloud for Customer
• Cloud Platform Integration 

1. Login to C4C.
2. Go to Webservice Message Monitoring.
3. Check the failed outgoing message with error "HTTP 500 Internal Server Error" or 401 (Unauthorized).
4. Navigate to error log, you will see:  HTTP Code: 403 or 401 ( ) - An internal error occurred during message processing. 

The C4C Client (M) certificate has been renewed and/or the Root and Intermediate certificates of the C4C client certificate (M) are not available in the CPI keystore.

1. In case you were not informed about the C4C certiifcate renew, please follow the steps outlined in the KBA 2585332 - Tenant Certificate Renewal for SAP Cloud for Customer.
2. Download the renewed client Certificate(M-User certificate)  from C4C Work Center: Administrator → Communication Certificates → Download Tenant Certificate.
3. Upload the renewed C4C client certificate in the CPI as mentioned in our blog: How to Setup Secure HTTP Inbound Connection with Client Certificates / Cloud Integration on CF - How to Setup Secure HTTP Inbound Connection with Client Certificates.
4. Add the attached certificates (SAP Cloud Root CA) to the CPI keystore.

Online Help page: SAP Cloud Platform Integration

 CPI CERTIFICATE C4C HTTP 403 401 500 , KBA , LOD-C4C-NET , Network Connectivity and Certificates , How To