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Use this topic for all email delivery questions

Bounce Classification Codes

February 2020

Bounce Classification Codes Following is a list of bounce classification codes and their meanings Classification Name Description Category 1 Undetermined The response text could not be identified Undetermined 10 Invalid Recipient The recipient is invalid Hard 20 Soft Bounce The message soft bounced Soft 21 DNS Failure The message bounced...

Dedicated IPs - full-circle reverse DNS and EHLO hostnames on SparkPost

February 2020

Dedicated IP addresses issued from SparkPost address ranges automatically have Full Circle Reverse DNS

Dedicated IP Pools

February 2020

Dedicated IP addresses are available for any account with the exception of the FREE plan with no credit card details on file Any new dedicated IP address added to your account will have a neutral initial reputation which means that you will be responsible for properly warming up your new...

Deliverability Analytics

October 2021

Get the full picture of your email lifecycle by combining your sending, engagement, and deliverability data into a single view. Deliverability Analytics empowers you to make effective, timely, data-driven, and strategic decisions to maximize the success of your email program.

When sending to Gmail subscribers I see this error: "We've found that lots of messages from are spam"

February 2020

You are receiving this error because Gmail uses the return path domain for that error message However it is your from domain that the reputation is actually referencing We have clients sending to Gmail from the same return path and I Ps that are not experiencing inbox issues Steps Towards...

Global Suppression List

February 2020

When deploying an email campaign you may notice that the number of recipients injected may not match the number of recipients targeted This is due to suppressions that are applied prior to the actual deployment Your injection list is first bounced against your own suppression list opt outs hard bounces...

IP Warm-up Strategy Overview

October 2020

IP warming is the process of methodically adding email volume to a new IP address gradually over several days and weeks in order to establish a positive sending reputation with mailbox providers. Mailbox providers view email from a new IP address as suspicious until...