Error while running logstash file

D:\logstash-7.4.2\bin>logstash -f sample.conf
Thread.exclusive is deprecated, use Thread::Mutex
Sending Logstash logs to D:/logstash-7.4.2/logs which is now configured via log4j2.properties
[2019-11-24T22:49:41,889][WARN ][logstash.config.source.multilocal] Ignoring the 'pipelines.yml' file because modules or command line options are specified
[2019-11-24T22:49:41,918][INFO ][logstash.runner ] Starting Logstash {"logstash.version"=>"7.4.2"}
[2019-11-24T22:49:42,693][INFO ][logstash.config.source.local.configpathloader] No config files found in path {:path=>"D:/logstash-7.4.2/bin/sample.conf"}
[2019-11-24T22:49:42,713][ERROR][logstash.config.sourceloader] No configuration found in the configured sources.
[2019-11-24T22:49:43,225][INFO ][logstash.agent ] Successfully started Logstash API endpoint {:port=>9600}
[2019-11-24T22:49:48,150][INFO ][logstash.runner ] Logstash shut down.

D:\logstash-7.4.2\bin>logstash.bat -f sample.conf
Thread.exclusive is deprecated, use Thread::Mutex
Sending Logstash logs to D:/logstash-7.4.2/logs which is now configured via log4j2.properties
[2019-11-24T22:51:52,369][WARN ][logstash.config.source.multilocal] Ignoring the 'pipelines.yml' file because modules or command line options are specified
[2019-11-24T22:51:52,393][INFO ][logstash.runner ] Starting Logstash {"logstash.version"=>"7.4.2"}
[2019-11-24T22:51:53,380][INFO ][logstash.config.source.local.configpathloader] No config files found in path {:path=>"D:/logstash-7.4.2/bin/sample.conf"}
[2019-11-24T22:51:53,406][ERROR][logstash.config.sourceloader] No configuration found in the configured sources.
[2019-11-24T22:51:54,255][INFO ][logstash.agent ] Successfully started Logstash API endpoint {:port=>9600}
[2019-11-24T22:51:58,945][INFO ][logstash.runner ] Logstash shut down.

What is unclear about that message?