A Guide On Email Bounce Codes – You Must Know

Introduction

In email marketing, grappling with email bounce codes can test a marketer’s patience. So, mastering these tricky codes is paramount to a neat and clean email list.

What are Email Bounce Codes?

Put, email bounce codes are messages from a mail explaining why an attempted email delivery failed.

So, these email bounce codes specify “soft bounce” – a temporary hiccup or a “hard bounce”- an issue that can’t be resolved.

So, the codes pinpoint various issues, from an overcrowded inbox to non-existent email accounts.

Difference between Soft Bounce and Hard Email Bounces

Soft bounces highlight transient issues like a filled-up mailbox or minor errors in the recipient’s mail server.

Hard bounces represent irreparable issues like non-existent recipient inboxes.

The usual course of action? So, Retry ‘soft bounced’ addresses and strike off ‘hard bounced’ addresses for all future campaigns.

On the off chance your provider doesn’t, you should manually prune such addresses from your list since hard bounces can raise red flags with email clients and hinder your deliverability.

Email bounce codes for soft bounce

So, beneath are the definitions of popular email bounce codes for soft bounce:

• 4.0.0 – A nonspecific temporary failure, but temporary nonetheless!
• 4.1.0 – Someone will resolve the vague, address-related issue soon.
• 4.1.1 – Off-target mailbox address: the mailbox address you’re trying to reach is either incorrect or doesn’t exist.
• 4.1.2 – Off-target system address: so you’re trying to find a system that isn’t there or doesn’t check out.
• 4.1.3 – Incorrect mailbox address format: The mailbox address syntax doesn’t follow the script
• 4.1.4 – Unclear destination mailbox address: So, the address entered could be one of several places.
• 4.1.5 – Refusing to receive: This mailbox won’t take your message, though the address is correct
• 4.1.6 – Mailbox has moved: like a turtle, it moved its home; so unavailable for now
• 4.1.7 – Incorrect sender’s mailbox syntax: your syntax is off in your address
• 4.1.8 – Incorrect sender’s system address: so your system doesn’t seem to exist at the specified place

• 4.2.0 – Full House: So, unable to cram more in, the recipient’s mailbox is heaving at the seams
• 4.2.1 – Disabled, refusing mails: so this particular mailbox not currently responding to messages
• 4.2.2 – Passive mailbox: it just won’t take any new messages right now
• 4.3.0 – Full-up storage: filled with existing mail, can’t take anymore.
• 4.3.1 – System’s Full: a bit light on storage hmm? so too jam-packed for anything else
• 4.3.2 – Messages not in flavor: doesn’t feel like engaging in network messages currently
• 4.3.3 – Incompatible features: the system just isn’t feeling up to taking your unique message

Additional Email Bounce codes

• 4.4.0 – Unknown network or routing status: something’s off, but we can’t say specifically what
• 4.4.1 – Unresponsive host: so the recipient’s email server has dozed off on duty
• 4.4.2 – Bad connect: connection’s as choppy as a sailor’s speech in a storm
• 4.4.3 – Routing server botched: A flop performance by the routing server while directing the message
• 4.4.4 – Routing lost: unable to decipher the roadmap to send this message
• 4.4.5 – Jammed mail system: it’s rush hour on the main highway and messages aren’t moving
• 4.4.6 – Stuck in a circle: Merry-go-rounds are fun, but emails looping through routes are not.
• 4.4.7 – Too slow, time’s up: that message didn’t make it in time, better luck next time
• 4.5.0 denotes an ambiguous protocol problem.
• A 4.5.1 error means that the recipient’s server does not recognize the command.
• 4.5.2. means a syntax error in the command.
• 4.5.3. means a message sent to too many recipients 
• 4.5.4. means command arguments are invalid.
• 4.5.5 error means that the server signals the protocol versions as incorrect.
• 4.6.0. means that the server codes any unmentioned media failures.
• A 4.6.1 error denotes that the server does not support your media type.
• 4.6.2 means that a required conversion is prohibited.
• 4.6.3 means that a critical conversion isn’t supported.
• 4.6.4. means Converted media with data loss 
• 4.6.5 means If your media failed to convert,
• 4.7.0. means an unclear security concern 
• 4.7.1. means Delivery not approved and message rejected 
• 4.7.2. means Mailing list expansion is forbidden 
• 4.7.25. so this means If an anti-spam filter pauses your email.

Next up, email bounce codes for hard bounce: 

• 5.0.0  Means General permanent failures with no attached specific register 
• 5.1.0  Means An unclear permanent failure links to the address 
• 5.1.1 means the recipient’s email address is non-existent,
• 5.1.3.  Means  In case of a recipient’s address syntax being invalid, 
• 5.1.4 means A vague recipient email address
• 5.1.5.  Means If the recipient’s email address is valid but not accepting emails, 
• 5.1.6 means the mailbox is no longer available, and no forwarding address was provided.
• 5.1.7 – Sender’s mailbox address syntax ain’t right: so the way the sender puts down their mailbox address doesn’t hold water.
• 5.1.8 – The sender’s system address sideways: the sender’s address system just won’t cut the mustard.
• 5.2.0 means the mailbox is temporarily unavailable and not accepting messages. Even mailboxes need a break.
• 5.2.1 – Mailbox full: Can’t squeeze in another message into that recipient’s mailbox.
• 5.2.2 – Message acceptances are on hold for the mailbox. A vacation notice, perhaps?
• 5.2.3 – Super-sized message alert: the recipient’s email server can’t stomach the message size.
• 5.2.4 – Problem in expanding mailing list: a hiccup when trying to grow the mailing list.
• 5.3.0 – Mail system storage bursting at the seams.
• 5.3.1 – System storage for mail – belly up: so too little storage left for comfort.
• 5.3.2 – Are there any network messages that won’t fit into the system?
• 5.3.3 – System features exceeding capacity to handle them: so who can explain the mysteries of compatibility?
• 5.3.4 means the system cannot handle this message due to size limitations.
• 5.4.0 – Network or routing status – a dark cloud hovering over us without any explanation.
• 5.4.1 means the recipient’s email host is not providing any information, which can be quite frustrating.
• 5.4.2 – Substandard connection quality: Is it the long winding cables then?
• 5.4.3 – Message routing hit a brick wall: the system needs a GPS, don’t you think?
• 5.4.4 means the system cannot route the message, possibly because the routing path is unavailable.
• 5.4.5 – Mail system bottlenecked: It just can’t keep up.
• 5.4.6 – Round and round: a routing loop in play.
• 5.4.7 – All out of time: so maybe this mail’s traveling by a sundial clock?

Additional email bounce codes for hard bounce

• 5.5.0 means the protocol status is unclear or not properly defined, leaving the issue as an enigma to be resolved.
• 5.5.1 – The recipient’s server didn’t take a shine to this command.
• 5.5.2 – Who made this command? Broken syntax: Surely, there are no shortcuts to good grammar?
• 5.5.3 – Too many addresses: there were excessive recipients for the message.
• 5.5.4 – Incorrect command inputs: invalid command arguments were used.
• 5.5.5 – Protocol mismatch: a wrong version of the protocol was utilized.
• 5.6.0 – Unspecific media mishap: an undefined error occurred with the media.
• 5.6.1 means the media type is unsupported and not accepted by the server.
• 5.6.2 – Forbidden conversion: necessary media conversions are not allowed.
• 5.6.3  means the server does not support the required media conversions.
• 5.6.4 – Imperfect conversion: converted media but with data loss.
• 5.6.5- Conversion flop: failure in converting media happened.
• 5.7.0 – Ambiguous security status: security problems undefined.
• 5.7.1 – Unauthorized dispatch, rejected message: so the delivery wasn’t authorized, resulting in message rejection.
• 5.7.2 – List expansion denial: mailing list growth is not permitted.
• 5.7.3 – Impossible security change: necessary security alterations cannot be made.
• 5.7.4 – Missing security features: required security aspects aren’t supported.
• 5.7.5 – Encryption breakdown: an encryption failure occurred.
• 5.7.6 – Unsupported encryption algorithm: so the chosen encryption method isn’t approved.
• 5.7.7 – Message integrity derailment: the validity check of the message failed.

So, how to prevent email bounce?

Avoiding these email bounce codes is a matter of making sure your emails don’t bounce. The question is how?

So a good email bounce rate is usually 2% or less per email campaign. 

For starters, validate email addresses before you send

Always make sure your email list is clean and accurate.

Enter myEmailVerifier: A tool that allows you to check the validity of email addresses without actually dispatching an email.

How does it work to prevent email bounce?

myEmailVerifier employs precise syntax checks, investigates DNS and MX records, and employs intelligent algorithms to initiate a connection with the recipient’s email server. It’s sort of like a test run. So in a nutshell, no more annoying network messages and unnecessary bounce codes.

Divide your email lists

Your followers are different. They shouldn’t receive the same treatment.

Get personal with your emails. Divide your lists to send content that speaks to each reader. It drives engagement and reduces the chances of email bounce.

Check on your email deliverability

myEmailVerifer can handle this job for you.

It’s a tool that lets you test where your emails land, check their authentication and keep an eye on blocklists.

A keen understanding of SMTP email bounce codes and a tab on blocklists steer clear of potential fires.

Keep easily recognizable sender names and email addresses

Your sender name and email should be familiar to recipients.

The familiarity helps them identify your emails and primes them to not consider them spam.

Select a trustworthy email service provider

Picking a popular email service provider (ESP) certainly improves your deliverability. Such as a bulk email verifier for verifying email lists.

Their ties with the mail server ADMINS and better handling of retries with the mail server up your game.

Conclusion on email bounce codes

Making sense of email bounce codes is a big win for any email marketer. What’s better than knowing how to read secret codes, right?

You decode, understand, and find problems and solutions, all in the interest of successful delivery of your emails. Now, doesn’t that sound like a plan?

Navigating soft bounces caused by transient issues or addressing hard bounces indicating grave concerns won’t be monumental tasks. Because you’ve got the knowledge in your arsenal.

The next email bounce notification you get won’t throw you off guard. Instead, you’ll turn the bounce into a touchdown. And keep your emails going.

And if you need the highest level of assistance to guard against email bounces? myEmailVerifier got your back. Now, how about that?