For the log you could search in C:\ProgramData\Qlik\Sense\Log\ or
For the error in section acces, can you pass what you recently add in your code?
try to put and exit script in some part to the script to know and discovery where the error is.
The Log file in is the same directory as the model. It will have the same name but a txt extension.
e.g. if your model is called Sales.qvw then the log file is Sales.txt
To make sure you are creating the log file check that under the Settings menu then Document Properties option and on the General tab you have the second checkbox ticked which is Generate LogFile
When you have created your section access then you must check that you have also set these properties.
Again, under the Settings menu then Document Properties option and on the Opening tab then half way down the tab you need to check the checkbox for Initial Data Reduction Based on Section Access and the checkbox for Strict Exclusion too.
This should be enough for the manual reload.
For scheduled reloads you will need to provide the Username and Password for the reload.
You do this in the QlikView Management Console under the Documents tab (select your model you want to reload) then on the Reload tab at the bottom tick the Section Access checkbox and set the username and password.
Also, make sure that you have an admin set up in the section access otherwise you could lock yourself out!
Hope that helps,
Have you added a System user to the Section Access:
ACCESS, USERID, REDUCTION, OMIT
You are using your own account to load the app from the script, but you should allow the system user (which is running the scheduled tasks) to do the same.
Hope it helps.
Take a look on your script if you inserted the Qlik Sense users services, because this user is responsible to access the app and reload it.
Also, look this help because is necessary add some other local users like INTERNAL\SA_SCHEDULER
Please, mark the CORRECT and/or HELPFULL comments.