Gmail SMTP error - Temporary block?

Question

I am using Gmail servers to send email from my system, with a program. Recently I started getting errors like this:

Data command failed: 421 4.7.0 T

Answer 1

This error occurs if you are using scripts to send emails in quick successions. An easy way out is to apply a sleep timer in between sending emails.

I applied a timer for 1 second between each successive email.

import time
time.sleep(1) // equivalent to 1 second sleep