[RESOLVED]: SMTP Error "554 Transaction Failed"

[RESOLVED]: SMTP Error "554 Transaction Failed"

Sending and receiving Emails these days is an everyday task. Life is incomplete without it. But Email technology is more than the simplicity there is on the surface. Under the hood, many servers and protocols keep the environment running which in turn facilitates the exchange of emails from one ID to another. When sending an email, it’s not uncommon to encounter the SMTP 554 Transaction Failed Error. In this article guide, we’ll explain the top 3 reasons that result in this error and how you can solve it.

What is SMTP 554 Transaction Error?

SMTP 554 occurs when you try sending an email to a recipient and the transaction fails mid-way. These errors are, in fact, difficult to deal with. This is because of the unclear error codes. When sending an email, here what goes behind the scenes:

When you send an email, the sending process starts with you, the sender. This is sent to your MX and then to the recipient’s MX. Only after then is it forward to the recipient’s inbox. If you’re unaware, MX stands for Mail Exchange Record. The MX records are hosted where your nameserver is hosted, So you can see there are four parties involved in an email transaction.

All the parties have their own protocol they follow to verify the authenticity of the transaction, and especially the sender. In case of an error at any level, the mail transaction is rejected. This throws the 554 Transaction error.

There are various type of 554 error and it’s not a catch-all for all email errors. Some of them are:

How to Fix the 554 Transaction Failed Error?

There are many such errors related to 554. The most common message you’re likely to get is:

We’ll take a look at the top 3 errors and how to fix them.

• Recipient Error

The main reason why people get this error is because there’s an error at the recipient side, in this mail server. This also includes:

• A type error you’ve made.
• An invalid MX entry for recipient domain address.
• Filters or custom firewalls installed at the recipient server.

To fix this, you first need to check for the typo error. So double check if you’ve typed the domain address correctly. Once that’s confirmed and out of the way, next place to look at is MX records. Use the following commands to view the details:

Then check for the connection to the mail server of the recipient. Use the following code for this:

This will reveal if the MX entries are correct or there are any connection problems. Also if there’s any custom blacklist in place. Once the problem is spotted, recommend necessary changes to be made at the recipient’s server.

• Suspicious IP Reputation

The next common reason why senders receive the 554 Transaction Failed error is because their email is hosted on a server that has a bad reputation among DNS providers. This can be because of repetitive spam instances, or open relays, or irregularities in the mail server. Because of this, spam monitoring systems like DNSSBL will blacklist your IP server.

If that’s the case, you need to find out the source of the spam and fix it. You can use services like Mxtoolbox.com to find the source.

Once fixed, send a request to the spam monitoring systems to delist your mail IP server from the blacklist.

• Poor DNS Record

If the DNS records of your domain address are problematic, then the recipient server will reject the incoming emails. The recipient server will check for DNS records like PTR, DKIM, and SPF to authenticate your validity. If there’s a mismatch, the email will not be delivered.

Therefore, you need to dig into these records and make sure there’s no mismatch. You can use any of the DNS lookup services for this.