If you are trying to send emails and get a message like:
421, response: Unexpected failure, please try latter
then it could be a temporary issue. If the message says:
"No action is required on your part. Delivery attempts will continue for some time, and this warning may be repeated at intervals if theĀ message remains undelivered. Eventually the mail delivery software will give up, and when that happens, the message will be returned to you."
If you experience this error everytime, please contact AryanIct so we can test your email and POP client settings.