Change to Mail Service in Apps Script

In a blog post by Saurabh Gupta on the Google Apps Developers Blog, a change to the Mail Service in Google Apps Script was announced, effective September 13, 2016. This change requires users with free public Google Accounts, as well as Google Apps for Education and Google Apps Free edition users, to have Gmail access to send emails using Apps Script's Mail Service. Previously, MailApp's sendEmail method did not require the user to have a Gmail account, unlike the GmailApp's sendEmail method. After the change, users can enable Gmail on their accounts to comply, with Gmail becoming the primary address of their Google account. For administrators of Google Apps domains in Education and Free editions, Gmail can be activated via the Admin console. The update does not necessitate any code changes, allowing continued use of MailApp, provided users sign up for Gmail. Despite the potential disruption, the update was made with careful consideration.