Monitoring Email Delivery Failures

Imagine you send out a monthly newsletter containing some financial news. Users sign up for this list using your website. Over time, this list may become stale, and many addresses end up in non-deliverable messages. This plugin maintains a list of email addresses that fail to deliver.

Difference Between Failed Deliveries and NDRs (non-delivery report)

There are two types of non-deliveries:

  1. Emails that fail to deliver because the recipient is invalid
  2. Emails that generate a non-delivery report

Although both categories appear to be the same, there is a subtle but important difference. The first failure occurs when your email server is unable to deliver the message to the recipient's SMTP server. For example, if the domain name is misspelled, and as a result, no MX record is found. In the second case, your email server can deliver the message to the recipient's SMTP server, but a non-delivery report is generated at a later time.

The first case is more straightforward to handle because your email server will be immediately aware of this failed email. The latter category is a bit more complicated because your server will receive an email about a non-delivery and will now extract the recipient's information from this NDR.

Creating a Failure Monitor in Xeams

A failure monitor is typically created for emails that you send out on a periodic basis. Two attributes about these emails stay constant:

  1. The sender's email address
  2. The email's subject has a particular pattern. For example, the subject of these emails may read: Stock Picks for July.

Since these two attributes are constant, they are used to define a monitor in Xeams.

Steps

  • Click Home > Plugins > Delivery Failure Monitor
  • Assign a friendly name, the email address of the sender, and a pattern for the subject. For the above example, you can enter a phrase like "Stock Picks for".

Downloading Data

You will be able to download a list of recipients for every monitor you create. The downloaded data is comma-delimited and contains two columns:

  1. A timestamp when failure occurred, which is a 64-bit long integer containing a date in milliseconds after Jan 01, 1970 (epoch date).
  2. The recipient's email address