A major and minor return code of 0000 indicates that the operation requested by your program completed successfully.
Most of the time, the server issues no message. In some cases, the server might use a diagnostic message to inform the user of some unusual condition that it cannot handle, but which might be considered an error under some conditions. For example, it might ignore a parameter that is not valid, or it might take some default action.
For communications devices, a major return code of 00, indicating successful completion with data received, is accompanied by a minor return code that indicates what operation the application program is expected to perform next. The nonzero minor does not indicate an error. No message is issued.