Recipient address rejected: User unknown in local recipient table

This error is returned by the mail server when it cannot deliver a message because the recipient mailbox does not exist on the destination server.

In simple terms, the server does not recognize the email address you are trying to send to.

Common causes

This issue usually appears in the following situations:

• the recipient mailbox was deleted
• the email address was typed incorrectly
• the domain has no active mailbox configuration for that address
• the recipient has moved their email service to another provider

How email delivery is checked

When you send an email, the receiving server verifies whether:

• the domain exists
• the mailbox is active
• the address is correctly configured

If any of these checks fail, the server rejects the message with this error.

How to fix the issue

1. Check the email address

Verify that the recipient address is spelled correctly, including:

• username
• domain name
• dots and special characters

Even a small typo can cause delivery failure.

2. Confirm mailbox existence

If possible, verify that the recipient mailbox still exists on their email server.

If the mailbox has been deleted or disabled, the message cannot be delivered.

3. Try an alternative contact method

If the address is correct but still rejected, the recipient may have:

• changed providers
• migrated their mailbox
• disabled the account

In this case, request an updated email address.

Practical implications

• the issue is always on the recipient side, not the sender
• messages are not delivered or stored in a queue
• retrying without changes will not resolve the error

Summary

The “User unknown in local recipient table” error means the recipient email address does not exist or is not recognized by the destination mail server. It is typically caused by a typo, deleted mailbox, or inactive domain configuration.