Install as a Windows service

[theizty]

Hello, 

I have a few question below on running windows as Service.

1. When I install window service, do I need to change the Service user from LocalSystem to one of our Service account? 
2. I tried creating a task which RoboIntern is running a VBA macro. As per observation, the macro run successfully but when I check the status from the GUI, 
It says error and when checked to the logs, I got 'Executed with result 'Error' and message exception from HResult: 0x800A9C68'

Thanks in advance