The logging level of the TIBCO Spotfire Web Player can be increased when investigating issues by using the "Enable Monitoring Logging" option on the Monitoring & Diagnostics page. See the reference
Logging and exporting monitoring diagnostics for more details. This will increase the logging level to DEBUG until the service is restarted or manually change. To restore the logging levels to what is specified in the log4net.config file, you can use the "Restoring Monitoring Logging" option.
In versions 7.12, 7.13, 7.14, and 10.0, when "Restoring Monitoring Logging" is selected to switch back the logging configuration, the monitoring logging status on the Instances tab does not switch back to "Monitoring logging (Currently off)" and instead remains set to "Monitoring logging (Currently on)", as seen here: