Subject: Message Delivery Delay
Message delivery has been delayed to the following recipients:
Recipient: [SMTP:**********]
Reason: Remote SMTP Server Returned: 450 too many emails from this sender, please try again later
You may get or are getting this notification if you are trying to sent emails to a large amount of recipients within a short period of time. The reason for this is by default your email service at Caorda is subject to a rate limit. Similar to other large vendors (GMail, Outlook.com) we limit the number of emails you can send overtime. This is used to prevent your mail account or website from being used to mass mail, be it on purpose or not.
Caorda has the following restriction setup:
- 100 emails allowed in the last 30 minutes
This is a constant moving window, not a timer that resets every 30 minutes. If you were to send 90 emails just now, you will only be allowed to send another 10 emails in the next 30 minutes before the original 90 emails are no longer being counted towards your limit. Overall this allows you to send up to 4800 emails in a 24 hour period.
To give you some comparison:
- Gmail limits you to 2000 emails in a 24 hour period
- Outlook.com limits you to 5000 emails per day
If you are receiving the message don’t worry, “Message Delivery Delay” is exactly how it sounds, our mail system has accepted the email from your website/email client and the email will be delivered when it can.
If you are wanting to exempt an email address from being rate controlled you have have a couple options.
- For small list reach out to your Caorda account manager or Caorda Support, for a small fee per email address and an acknowledgement that the emails generated by you are not spam we can remove the rate limiting on your email address.
- For larger lists we have other services that may better fit your purpose.