I'm using the XMLTV GUI grabber to get Schedules Direct (North America) TV Program Schedule Guide (EPG) information for my PVR software on Windows 10. I have no problems interacting at all. Data files are generated containing all desired information.
However, if they run as a scheduled task, either XmltvConsole.exe or XmltvGui.exe / Grab will not retrieve data and log messages such as
5:15:01 - 0 programs found ... 5:15:02 - No programs found, aborting xml writing
This would normally indicate that no channels are configured for the selected grabber. Of course, I see in the GUI that I have added every available channel to my selected channel list.
I've made sure that the scheduled task runs as my user account, whether I'm logged in or not, and I've tried several settings for the "Run In" box in the scheduled task: I've used the program directory under C: Program Files (x86), the user folder of my user account, and nothing at all. I have checked that the task is done correctly.