All zenon components write in the background messages to joint log files, which are stored in the folder '%programdata%\COPA-DATA\LOG'.
These files can be read and configured with the Diagnosis Viewer.
You can modify the logging level of a component by clicking 'Client Configuration' in the 'Settings' menu and then selectin the respective process name.
Attention: Set the logging parameters wisely as the time frame of the LOGs decrease when you increase the detail of the written logs.
You can also find LOG files in SIC in the folder 'Platform > Versions > Version XXXX > Directories > LogDirectory'.