I have come across a similar issue when I execute the Denodo Monitor start-up file without setting my JAVA_HOME path.
In order to resolve this issue I would suggest you to set the **JAVA_HOME **path pointing to **<DENODO_HOME>/jre** and then configure the Denodo Monitor tool by following the steps mentioned in the [Configuring the Denodo Monitor
](https://community.denodo.com/docs/html/browse/8.0/en/vdp/administration/monitoring_the_virtual_dataport_server/denodo_monitor/configuring_the_denodo_monitor#configuring-the-denodo-monitor) section of the Virtual DataPort Administration Guide.
Furthermore, try executing the denodomonitorstartup.bat file in the command prompt to see if it is throwing any error.
Hope this helps!