Email Template - too many connections - need pooling
Our app is using the EmailTemplate module to send emails when forms are filled out as well as automated emails that send out a few dozen emails at a time. The latter often fail with a message from our gmail server 454 4.7.0 Too many login attempts, please try again later. It turns out EmailTemplate opens and closes a connection to the email server for every single email. The problem is not the number of emails sent. The problem is the number of connections. Is there anything that can be done with the Email Template module that opens a connection once and closes it once, looping through all the emails in between, so only one connection is opened for multiple emails?
If you are sending a lot of emails, you really need to look at using a bulk email provider. They are built to handle a large volume of outgoing email, and will help ensure your emails are delivered.
I've used SendGrid and Mailgun successfully from Email Template in the past, but other companies offer similar services. Gmail isn't really meant for this.
I know this isn't really the answer you are looking for, but it's the solution I use, and it works.