Google Script Error: You do not have permission to call openById

Question

I am trying to send a mail with attaching a file available in my google drive using following google scripts

var file=DriveApp.getFileById(\'1qZVK0UZ1jLbDdj1         


        

Answer 1

I ran into this same issue, but felt it was a little silly to have to use the FormResponses Sheet to get the submission event (I mean there's a trigger on the Form Apps Scripts for a reason, right?).

All I had to do was to Remove and Re-add the trigger for From form --> On form submit. When I added it, challenged me for OAuth permissions to view and use my google drive.

Immediately after this, I was able to run on a Forms Apps Script Submission trigger again.