Some emails bouncing with 450 4.7.1 error

A

Alvin63

Well-known member
This happens once a week when the weekly newsletter goes out. About 12 emails to 12 members bounce with this error and come up as a server error. I only have about 250 members at the moment, so won't be exceeding the email quota (I think). I noticed the IP address is an IPV6 one. Any ideas? I'm wondering if they're all gmail addresses and google doesn't like something. I have DMarc, SPF and DKIM set up via cloudflare.

Edit it shows the email addresses in the server error - they're not all gmail - there's a whole range of email providers in there: gmail, hotmail, icloud, yahoo.
 
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Alvin63 said:
This happens once a week when the weekly newsletter goes out. About 12 emails to 12 members bounce with this error and come up as a server error. I only have about 250 members at the moment, so won't be exceeding the email quota (I think). I noticed the IP address is an IPV6 one. Any ideas? I'm wondering if they're all gmail addresses and google doesn't like something. I have DMarc, SPF and DKIM set up via cloudflare.

Edit it shows the email addresses in the server error - they're not all gmail - there's a whole range of email providers in there: gmail, hotmail, icloud, yahoo.
Click to expand...

Just to add that I use gmail and I received your newsletter earlier today :)
 
What email provider are you using to send emails?

450 4.7.1 errors are related to reputation - the receiving servers are rejecting your emails because your sending reputation is bad.
 
It’s outsourced by the server. Had an issue once before when the IP for the email service was on a blacklist but they changed the IP when I told them. Checked the IP and it’s not on any blacklists. The error says something like recipients inbox full.
 
Using your hosting providers SMTP server is never a good idea these days - it is shared with all the other senders using that provider and you can almost guarantee that some of the users are abusing email sending - either deliberately or because they don't know what they are doing.

You really should use a dedicated Email Service Provider (ESP), to send emails - otherwise you're going to keep having deliverability problems.
 
Yes you're right. I'm signed up for a year or two although it wasn't that expensive. Isn't it the same with dedicated email providers? ie don't you also share the IP address with other users?

I did try and sign up with Amazon AWS once and gave up ha ha. Found it too complicated.
 
Alvin63 said:
Isn't it the same with dedicated email providers? ie don't you also share the IP address with other users?
Click to expand...

Yes, if you're a small sender, you'll need to use a shared IP - but given that ESPs reply on their ability to be able to send emails, they tends to be far more strict about keeping the reputation of their IP addresses in good order, compared to hosting providers. Hint: don't use an ESP who isn't strict on who they allow to send emails - you'll end up with bad sendability when other users trash the reputation of their IP addresses.

Once you're sending closer to 100K emails per month, you should be looking at a dedicated IP address for sending, which should greatly improve your sendability - assuming you're not abusing it yourself and maintaining good sending practices.

I'm spending US$75 per month on sending emails with SparkPost with a dedicated IP address and sending just under 100K emails per month and I have very few issues with deliverability.
 
Well I couldn't afford $75 a month :-) I'm paying about £20 a year. SPF, DKIM and DMARC are all set up in Cloudflare. But yes it could be the host is throttling. There are no email issues generally, just once a week when a newsletter goes out to everyone. About 12 out of 250 are rejected each week. I'll see this Saturday if it's stopped or a different 12! The last 12 I removed from the newsletter list just to see if it was those accounts particularly.

The email isn't directly from the server. The server outsources to another company for email.
 
Alvin63 said:
About 12 out of 250 are rejected each week.
Click to expand...

That's nearly 5%, which is pretty huge.

If you aren't immediately removing those emails from your mailing list, you will be hugely damaging your sending reputation.

Continuing to send emails to previously bounced, rejected, blocked or otherwise, email addresses is a sure sign of abuse (at your end) and will definitely get you blacklisted from specific providers.

Email is hard. It takes a lot of effort (and/or money) to get it right these days.
 
Thanks. It's only been recently and since I started doing weekly newsletters. Yes I took those 12 off the mailing list, although had another one bounced tonight - just a standard watched topic email to a well known member. Yahoo postmaster. It said I could contact the postmaster regarding it - although not sure how. Code 421 4.7.0 [TSO 4]
 
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