Unable To Relay Recipient In Non-accepted Domain

Are you facing any issue while sending emails where you see an error message stating you are an 'Unable to Relay Recipient'?

Sometimes while sending emails you may experienced a situation where you get an error message saying you are an 'Unable to Relay Recipient'. In this document, we have discussed what this issue is, how can you fix it, and how to prevent it from occurring in the future.

What is 'Unable to Relay Recipient'?

When a mailbox on a mail server tries to send email to the external recipient, the recipient server verifies if the sender is authorized or not. If the sender is not authorized, the server returns an error message - Unable to Relay Recipient.

This error occurs when the Recipient server is unable to verify the sender and as a result, it rejects the email sent by the sender.

The error message "Sender not authorized, unable to relay" is returned when the recipient server is unable detect your IP address or domain name which try to send the email.

How to Fix this issue?

For fixing the issue of 'Unable to Relay Recipient' you will need to do the following steps:

1. Check if the mail server is authentication before sending mail.
2. Check if the mail server is configured to use SMTP authentication before sending mail.
3. If the mail server is configured to use SMTP authentication, enter username and password.
4. Check the username and password entered whether they are correct.
5. Check if the FROM address you are using is from a valid domain
6. Check if the email address is within the same domain.
7. Check if the mailbox is within the same domain.
8. Ensure that port 25 or 587 is enabled on your server.

How to Prevent this issue?

To prevent this issue from happening in future, you need to make sure that the mail server is configured to use SMTP authentication before sending mail. Also, ensure that you are using an address from valid domains and that the email address is within the same domains.

Frequently Asked Questions (FAQ)

Q: What is 'Unable to Relay Recipient'?

A: When a mailbox on a mail server tries to send email to the external recipient, the recipient server verifies if the sender is authorized or not. If the sender is not authorized, the server returns an error message - Unable to Relay Recipient.

Q: How to fix this issue?

A: For fixing the issue of 'Unable to Relay Recipient' you will need to do the following steps:

1. Check if the mail server is authentication before sending mail.
2. Check if the mail server is configured to use SMTP authentication before sending mail.
3. If the mail server is configured to use SMTP authentication, enter username and password.
4. Check the username and password entered whether they are correct.
5. Check if the FROM address you are using is from a valid domain
6. Check if the email address is within the same domain.
7. Check if the mailbox is within the same domain.
8. Ensure that port 25 or 587 is enabled on your server.

Q: How to prevent this issue?

A: To prevent this issue from happening in future, you need to make sure that the mail server is configured to use SMTP authentication before sending mail. Also, ensure that you are using an address from valid domains and that the email address is within the same domains.

Q: What are the possible causes of 'Unable to Relay Recipient' error?

A: The possible causes of 'Unable to Relay Recipient' error are:

1. Mail server is not configured for authentication before sending mail.
2. Incorrect username or password is entered.
3. FROM address is not from valid domain.
4. Email address is not within the same domain.
5. Mailbox is not within the same domain.
6. Port 25 or 587 is not enabled on the server.