Profiler uses SendGrid for the delivery of mass and transactional emails to clients. You may notice status information regarding the emails – this is directly fed from SendGrid (our email provider) and the explanation of the statuses is below
(As taken from the SendGrid website) – https://sendgrid.com/en-us/blog/delivered-bounced-blocked-and-deferred-emails-what-does-it-all-mean
These four events may occur between the time you send your email and when it reaches the receiving server:
- Delivered: The receiving server accepted the message.
- Bounced: The receiving server denied the message, and SendGrid will suppress the recipient’s email address going forward.
- Blocked: The receiving server denied the message, but SendGrid won’t suppress the email address.
- Deferred: The receiving server delayed acceptance of the message.
Let’s take a closer look at each of these events to help you understand your email delivery performance better.
Delivered: Emails are successfully sent to the server
There’s a common misconception that delivered messages always make it to the recipient’s inbox. The truth is that when a message registers as delivered, it only means the receiving server has accepted the message—but it must still decide what to do with it.
Usually, the server’s options are to deliver the message to the intended inbox or redirect it to the recipient’s spam or junk folder. But in rare cases, a receiving server might instead choose to drop that message—meaning, delete it. When this happens, the recipient won’t be able to find the message anywhere—even in their spam folder.
The server decides where to put the message based on signals like the sender’s reputation and the email content. Senders that have excessive spam complaints or send content that inbox providers know generates high spam complaint rates are less likely to have their emails delivered.
However, having a high percentage of delivered emails is only one part of your campaign’s success story. Next, your emails need to make it to the recipient’s inbox.
Bounced: Emails are permanently denied by the server
If you’ve never had blocked emails, you might wonder, “Do blocked emails bounce back to the sender?”
While some in the email industry use terms like hard bounce and soft bounce to describe messages refused by the receiving server, SendGrid’s terminology separates returned messages into two categories: bounces and blocks.
Bounces occur when the receiving server returns a code indicating that there’s a permanent issue with that server or the recipient’s address. The most common reason for an email address bounce is that the address in question is invalid.
“Will emails bounce back if blocked?” The answer is yes—all emails sent to a invalid address bounce back to the sender.
Blocked: Emails are temporarily denied by the server
Blocked emails are similar to soft bounce emails. For these temporary rejections, the receiving server’s reason for refusing the message is unrelated to the sender’s address quality.
In SendGrid’s Event Webhook, blocks are identified by the bounce event under the blocked type.
Here’s an example of a blocked email message:Reasons for a blocked email message include:
- The sending IP or domain is on a denied list.
- There are spam-marked elements within the email content.
- A technical issue occurred between the two servers when you attempted to send your email.
High spam complaint rates can lead servers to filter more emails from a particular sender to the spam folder and can result in email blocks. If you see many blocked messages, this can indicate damage to your sending reputation.
Deferred: Emails aren’t immediately delivered to the server
A deferred event, or deferral, occurs when the server temporarily limits access to its system. It works much like a telephone’s busy signal.
But this doesn’t mean that your message won’t get delivered—only that it won’t get delivered immediately. Some of the most common reasons for a message deferral include:
- The inbox provider sees too many spam complaints for delivered emails from the sender.
- The receiving server has technical issues.
When an inbox provider defers your email, SendGrid will still attempt to deliver your message for up to 72 hours. If your message gets deferred for more than 72 hours, it will get blocked and a block event will register. However, if the message gets successfully delivered within the 72-hour window, it’ll register as a delivered event.