There are two log files that can be referenced for troubleshooting issues.
NutServer Log files
Location: C:\Program Files\Nuts\NUTbookService
File name: NUTbookService.Log.YYYY-MM-DD.txt
The NutServer log files will contain information regarding the processing of data files and other critical system operations. These log files can be found under the installation path\Nuts\NutbookServer folder. By default the installation path on a typical install is C:\Program Files\Nuts\NUTbookService. The log files are names daily as NUTbookService.Log.YYYY-MM-DD.txt
NutManager client log files
The NutManager client log files will contain information regarding the user interface, functions that are application bound, and CloudAx information.