Verify if the log file is enabled, open QlikView Desktop Client > Settings > Document Properties > General > enable "Generate Logfile & Timestamp in Logfile Name"
Run reload > *.log will be generated where *.qvw is stored or in the task log location
Example:
QlikView Plugin issues such as tunneling and open document errors:
Add Log=1 in the connection string example: CUSTOM CONNECT TO Provider=QvSAPReportConnector.dll;ASHOST=MySAPServer;SYSNR=30;CLIENT=800;Log=1;XUserId=FUXaKSJMDLOB;XPassword=YNYLdYRNJbaMXUVMXTWB;"; Default path for the generated log file is %PROGRAMDATA%\Application Data\QlikTech\Custom Data\QvSAPConnector\Log