2667924 - Access denied to resource ... on system ... In case this was a valid request, ensure to expose the resource correctly in your cloud connector.

An application fails to connect to a backend system that was exposed in SAP Cloud Connector. In the SCC logs, you can see the error:

Access denied to resource ... on system ... In case this was a valid request, ensure to expose the resource correctly in your cloud connector.

or

Access denied to system <hostname:port> In case this was a valid request, ensure to expose the system correctly in your cloud connector

or 

[RFC] error open connection: Opening connection to backend failed: Opening connection to <hostname:port> denied. Expose the system in your Cloud Connector in case it was a valid request.

SAP Cloud Connector

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