If a Message Broker is failing for non-obvious reasons (for example, it isn't running or out of memory), you can turn on tracing by adding the following lines to its STMessageBroker68.ini file:
setopt Trace_Level Debug setopt Trace_File log_file_path setopt Trace_Flags prefix,timestamp
The case of the option names is not important.
The log_file_path can be any file path, for example, C:\temp\MBTrace.log.
The Debug trace level is the highest (most verbose), so the trace file will grow quickly. The levels "info" and "warning" are successively lower trace levels (less verbose).