Quick tips to debug email errors

Need to debug a bounce back error when sending emails?

First, check the bounce-back email, normally this will give you the clearest picture as to what's wrong.
Sometimes it'll tell you the address doesn't exist, or there was a temporary issue, or maybe the domain doesn't exist so there was a dns issue or another specific issue, but other times it's a little more vague. Here's an example:

550 permanent failure for one or more recipients ([email protected]:blocked)

Ok so let's work out why was it blocked, maybe in a blacklist or it came across as spam?

Let's next ask, does this happen when sending from your email client or from your website.

If for example it's coming from your email client, you could check if your provider is having some issues:
BEfore evening needing to contact them, they likely have a status page, here's a few examples:
GoDaddy: http://status.godaddy.com/
Heart Internet http://www.heartstatus.uk/
Fast hosts: http://status.fasthosts.co.uk/

Also check if it's just to a specific email address or domain, e.g. if you're having trouble sending to a btinternet.com address, try sending to a hotmail address or gmail to test if that works.

It's also worth checking if you're in an email blacklist: https://mxtoolbox.com/blacklists.aspx

If you are, normally you can contact the blacklist site to find out why and get unblocked.

What If you can't send from your website?

Check if you need to setup reverse DNS?
https://mxtoolbox.com/ReverseLookup.aspx

Many email providers will block emails from sites that don't have or match their reverse dns check. It's a great way for them to avoid spam. & It's easy enought to setup rdns, just contact whoever maintains your site / server.

Check if your site has a SPF record setup but doesn't have your site's ip added?
https://mxtoolbox.com/spf.aspx

An SPF record indicates where email clients should accept emails from. Several services will even get you to set this up such as Outlook 365. But make sure the ip of the site is in here too else it'll start to reject emails from your site.

Need to find your IP to add to an SPF record?
https://mxtoolbox.com/DNSLookup.aspx

& if you're looking to test an SPF policy you've created, try this -> https://vamsoft.com/support/tools/spf-policy-tester

This only covers the tip of the iceberg of possible email issues but hopefully it'll give you a head start on some common issues. If in doubt Google the error message & if it's still not clear you can always contact support for whoever provides your email service.

Another option for issues sending emails from your site is to try using a 3rd party service such as Mailgun to handle sending emails. They will guide you through setting up an SPF record as well as providing logs for all emails sent. Plus they are free for up to 10,000 emails a month and still very cheap for emails sent above this.