Email Testing: The Good, The Bad and The Ugly
As a website design agency there is a very good chance that you offer email services. These may be a free addition to a website package or an optional paid extra. However you do it, email hosting is never a fun industry to be in. Until very recently we offered email services to our clients and over the years we have seen it all. In this blog post we will be looking at some common issues and email testing tools to help you along the way.
Email testing tools to make your life easier
You'll come across a lot of random email errors and user cases when troubleshooting an email issue. Let's look into some tools:
SMTP Error Codes
Email servers are very good at offering a brief look into the email problem. You will generally see a code such as 512 and a snippet of information such as "DNS Error: host server cannot be found for recipient.". Which in this case could mean that the DNS is not correctly set up for the domain that you are trying to email. The error code is normally part of a bounce message sent back to the sender, so keep an eye on that inbox in case any come through.
One major issue can be if your email server/servers gets added onto a blacklist or a list of blacklists. A blacklist is essentially a list of IP addresses that have been collected and are known for being bad - such as sending out lots of spam. Blacklists can be run by companies or organisations, there are public ones and also private ones that are maintained by the service provider such as Gmail or Outlook.
Luckily most blacklists will allow you to appeal your case and offer to remove you for free (some charge so watch out - we have seen ones £90!). Here are a list of websites which allow you to check if your IP address has been blacklisted. Try to use a few as some of these websites will show some blacklists that others do not.
A spam tester will analyse your email by checking a number of factors, it will give you a detailed analysis of how spammy your email may look to servers and how your email server is configured. A great tool for this is Mail Tester
which allows you to send them an email to a dynamically generated address. Here's how to use this tool:
- Go to the website home page - https://www.mail-tester.com/ . You should see something very similar to this but a different address:
- Now, send your email to that address. It can be from your Email Newsletter provider or just from your email software:
- Wait a few seconds and then click on the "Then check your score" button to get your results!
You will be given a score out of 10 (where 10 is a perfect email and 0 is a really spammy email). If your score is not a perfect 10 then you will be given the reason why below. Each reason will have more in depth information so just click on the "+" button. This tool will also check for blacklists as well.
Mail Server Tester
This tool is relatively basic but could help when troubleshooting an email issue. The SMTP server test
from MX Toolbox will test for a few key settings:
- SMTP Reverse DNS Mismatch
- SMTP Valid Hostname
- SMTP Banner Check
- SMTP TLS
- SMTP Connection Time
- SMTP Open Relay
- SMTP Transaction Time
Sometimes it can be handy to know some of the email jargon, this can help speed up the troubleshooting process:
- SMTP - Simple Mail Transfer Protocol
- TLS - Transport Layer Security
- DNS - Domain Name System
- MX Record - Mail Exchanger Record
- POP - Post Office Protocol
- Bounce - An email that is returned with an error e.g. "The email address no longer a exists".
- DKIM Signature - DomainKeys Identified Mail
- DMARC - Domain Message Authentication Reporting & Conformance
- SPF Record - Sender Policy Framework
- HTML - Hypertext Markup Language
- BL - Blacklist
Remember, Google and other search engines are your friends! Simply paste the error code into a search engine and you are bound to find a solution or recommendation. Sometimes you may not find the solution straight away but its always worth trying out different search terms - try adding the name of your email server at the end of an error message e.g. "[ERROR 512] DNS ... Postfix email server".
Please note: The tools we have suggested in this blog post may or may not help your email woes but we have found that they are defiantly worth trying. You must remember that these tools are not run by us, they are individual companies and organisations - they tools may change or stop working at any point.
Thank you for reading and good luck with your email server issues. Fingers crossed that you don't have any! If you found this post helpful or enjoyed reading it then please feel free to share it on social media or link to on your website.
If you have any ideas for future blog posts
, we'd love to hear about them! Send us an email
and we'll let you know if it gets added onto the website.