Authorization Error when using Google Apps Script MailApp.sendEmail, though already authorized

Question

I have a script in Google Apps Script that sends me an email using the MailApp.sendEmail() function. I ran it once in the editor and it asked me to authorize the script so I did. I then scheduled it to run with a project trigger, but when it does I get an error email from Google Apps Script that says: "Authorization is required to perform that action.".

Why is it getting an authorization error when running as scheduled vs running from the editor and how do I make sure it is authorized?

NOTE: I have the @OnlyCurrentDoc tag at the top of the script.

Answer 1

I think this is a known bug. To have update or progress about it, you may check out that link. Hope it helps