SAP Message S03439 - Cannot read systems for a solution (Error &1 &2)

Diagnosis
An error occurred while calling the function moduleDMD_GET_SYSTEM_INFO. The system cannot read the list of systems for aspecified solution.

System Response
Error 1: unable_to_open_model
Error 2: object_type_not_found
Error 3: no_authorization
Error 4: internal_error
Error 5: communication_failure
Error 6: system_failure
Error 7: Other

Procedure
Check the solution key and the RFC destination for the solution managersystem.