Execute NPrinting Task via HTML file via Qlik Sense Server

[Lennert]

So pretty much what I am trying to do is have an HTML file execute a NPrinting task by running a Qlik Sense App (Using Qlik Sense Server 12.44.1) . 

So open de Qlik Sense App > (auto) Run the script that opens the HTML > HTML flashes sends a POST to the NPrinting server to execute a task

The problem is that I can't open a file from running my Qlik Sense app, this is the error I get:  *see untitled.png*

For more info:

This is how I'll execute the NPrinting task (via html file): https://dzone.com/articles/nprinting-api-for-noobshow-to-trigger-a-task-with

Executing a HTML file in Qlik Sense (Server) should just be as straight forwards as "EXECUTE F:\NPrinting\TaskExecution.html", right?