4 Fixes for “Email Recipient Address Rejected” Error

We live in an era where digital communications are actively used. From social media to formal communication, from meetings to chats, digital communication serves. However, it sometimes runs into limitations. Users experience one such issue when using email to communicate: receiving a rejection message for the recipient’s address.

If you’ve encountered this recently or ever, this is a return message with error codes. The most common are 551 and 541. Although, perhaps you are puzzled over what this message and codes mean?

Continue reading the following sections; you can learn all about it in a few minutes.

Reasons for rejecting a recipient’s address

The most common reason you might encounter a recipient address rejected message is when you are trying to use an invalid email address. By valid, we mean that it either never existed or is no longer valid.

In either case, the email system will not be able to send the message. The reason is that he was unable to determine the recipient’s address. But this is one of several reasons that cause this problem. Let’s take a look at them briefly.

Incorrect E-Mail Address

Several email communication tools are smart enough to remember the email address you’ve used in the past. At the same time, there is always room for more. But all his efforts will be lost if you make typos in the email address. As a result, you receive a delivery failure message or related error messages.

Problems with DNS

DNS or Domain Name System is the ability to resolve domain names into unique IP addresses. This system uses a cache that can become corrupted or outdated over time.

If this happens, you may experience a recipient address rejection error with one or almost every email you try to send. This problem can occur with browser and various email applications. These include Google mail, Outlook, and more.

Anti-spam filter

An anti-spam filter is a great tool for excluding unwanted emails. Again, this is just a tool that can sometimes flag genuine emails or even external emails as spam conversations. In addition, it is individual for each user.

Thus, if your recipient has a mailbox spam policy, you may receive an address rejection message.

Microsoft 365 DBEB configurations

DBEB is a directory-based edge blocking available in the service network of Microsoft 365 organizations. It allows you as a user to reject emails to unidentified or invalid recipients.

However, in most cases this error occurs after changing the Exclaimer Cloud configurations. This blocking service works for online Exchange mailboxes. It also works without Exchange online mailboxes available to different organizations and their respective users.

4 Ways to Fix Receiver Address Rejection Error

Now that you know the possible causes of this error, let’s move ahead and fix them to fix the problem.

1. Use the correct recipient email address
2. Replay DNS Cache
3. Request to be whitelisted
4. Update Exchange Email Settings

1. Use the correct recipient email address

As simple as it sounds, you must ensure that the email address you are trying to connect with is valid. There are two possible checks for this:

1. Correct spelling

Let’s say you’re about to send an email to a new user, but during verification, you discover that you spelled it incorrectly. Or the system detected a problem and gave a “Recipient address rejected”error.

But if you didn’t send that email, you can always change the customer’s email address. As a result, the error message disappeared.

2. Use a valid email address

Even if you have previously connected to a specific email user, the system still gives you email errors.

One possibility is that the username or email address you have is no longer valid. Recipients may have updated their address or may have left this organization, so your email is not being returned.

2. Retry DNS Cache

As we have said, DNS uses a cache. It speeds up the process by saving previous behavior patterns for any task on your computer. But if it is not updated over time, it can become outdated or even corrupted. And it may be one of the reasons causing problems with the action you requested.

So let’s take a look at the steps to clear the DNS cache regularly. These steps will also include TCP/IP data updates.

1. Open a command prompt on the local computer as an administrator. You can search for apps or use the Windows key + X on your keyboard.

2. Use the following commands in the terminal one by one. Remember to press the Enter key after each of these commands.

3. After successfully running these commands, close all applications and restart your computer.

4. Now try to connect to your email client and check if that fixes the email blocked error.

If not, let’s move on to the next solution.

3. Request to be added to the white list

This is about an anti-spam filter that crashes your recipient’s mailbox. The only solution to this cause is to contact the interested party. You will have to manually ask them or the recipient to update their spam filtering on the spam rules tab.

After you’re done with these updates, try repeating the steps and see if you get a similar message. However, if that doesn’t turn the tide, move on to the next one.

4. Update your Exchange email settings

Microsoft 365 is a set of apps available to everyone in an organization. Therefore, if you or your recipient’s address belongs to an organization that uses this package, this section may help you.

Let’s start with the basics. DBEB is the default setting offered by Microsoft 365 and is instructed to block external emails. It can distinguish between external and internal email addresses by referring to Azure Active Directory.

Therefore, if any email addresses are stored in the public folder mailbox, they are treated as external. While they may be valid, you will have to take additional steps to remove the rejection error code.

Follow the steps below to apply the patch according to the public server hosting scenario.

1. For hosting on local public servers

Accordingly, we will take the necessary steps to update additional features on the Microsoft Azure Active Directory Connect screen. This will mark the public folder mailbox as valid for DBED. Steps:

1 Open the Microsoft Azure Active Directory Connect screen for your account.

2. Click “Additional Features”in the menu on the left. This will open the permissions in this section.

3. Check the Exchange Mail public folder by checking the box.

4. Save the changes that should resolve the unknown email recipient issue.

2. For public servers hosted in Exchange Online.

DBEB currently has restrictions on hosting public servers in Exchange Online. However, we have a workaround to achieve this for mail-enabled public folders.

As part of this workaround, you’ll update the mail flow so that emails addressed to the public folder no longer go through the Exclaimer cloud.

Let’s understand the following steps for this:

1 Sign in to Exchange Online.

2. Go to the “Mail Flow”option and click “Rules”. This will unlock many rules in the exchange.

3. Find “Define messages to send to Exclaimer Cloud”and click the edit button.

4. Click “Add Exception”and select the recipient and then the “this person”option.

5. Select all public folder mailboxes in the “Select Member Dialog”.

6. Finally, click “Add”and then “OK”for the changes to take effect.

Bonus Tip

Another workaround for hosting public servers in Exchange Online is to completely disable DBEB. While this may seem like a solution, it is not. This removes all email and IP filtering to prevent any email based security attacks. Therefore, we recommend that you do not disable the DBEB feature in Microsoft 365.

FAQ

Why is my Outlook mail being rejected by the server?

The recipient’s mailbox may have marked the sender’s address as spam. The mail server may also encounter technical issues while serving requests.

What does it mean that the recipient’s email server rejects the message?

Receiving this error message means that the recipient’s email server is unable to validate your email. This occurs when the sender’s mail server has disabled the SMTP server authentication feature.

How to fix 550 5.4 1 Recipient address rejected?

Several updates related to mail servers and your mailbox settings may be required to fix this issue. This may include updating domain configurations and updating DNS. You may also need to troubleshoot issues with a service in Exchange Online.

What does it mean? Recipient address rejected. Access denied?

This usually happens when the sender is outside of your local domain. To fix this, you need to update your MX record. You may also need to check your DNS hosting service to double check valid mail server configurations.