Exchange SMTP Error 550 5.7.1 Unable To Relay : Troubleshoot the Error
Exchange SMTP Error 550 5.7.1 Unable To Relay error indicates a non-delivery report of issues associated with email or email relay. It might be caused when recipients do not enable the relay feature and sender is unable to reach. Basically, the domain at the receiver end might have blocked the sender domain from message relay.
At the time of using Microsoft Outlook with the Exchange server, users might be facing several errors. One of the most common errors among all is SMTP errors, like error code 5.0.0, Unable to Relay, etc. Out of these SMTP error codes, there is a common error code i.e., 501 5.7.1, which occurs due to trouble while relaying messages via Microsoft Exchange server. It also denotes that user’s email client is unable to authenticate the email server.
Symptoms Indicating Exchange Email Error 550 in Detail
- Error code 5.0.0, 5.7.1, or 5.7.3 appears with failure in email delivery.
- You start with facing of hurdles while sending emails, after increasing domains.
- The Exchange machine begins sending unsolicited-type of commercial messages, which displays in an email queue.
Causes of ‘Exchange SMTP Error 550 5.7.1 Unable To Relay’ Error
This SMTP error occurs when an end user is trying to send messages to the outside domains. Following points denote the causes behind the error message:
- The outgoing email server is unable to determine the sender.
- Some authentication issues are there on the server that are blocking email sending process.
- The sender domain is blocked at the recipient domain end.
Measures to Fix 550 5.7.1 SMTP Error
The solution varies with the version of the Exchange server. So, first determine the server version and then, begin with the error resolving approach.
- For MS Exchange 2007 Users – You have to configure the Exchange server to accept and relay messages from the host. The permissions for submitting and relaying are listed in ‘Permissions Group’. Following permissions can be granted to authentic users :
- NT AUTHORITY\Authenticated Users {ms-Exch-SMTP-Submit}
- NT AUTHORITY\Authenticated Users {ms-Exch-Accept-Headers-Routing}
- NT AUTHORITY\Authenticated Users {ms-Exch-Bypass-Anti-Spam}
- NT AUTHORITY\Authenticated Users {ms-Exch-SMTP-Accept-Any-Recipient}
The option “Only the list below (mention the IP address)” is needed for those users who are unauthentic for the Exchange server. Such condition occurs when the application server is used that relay emails via Exchange. Well, following guidelines will help you in creating new SMTP Virtual server :
- Generate a new SMTP receive connector
- In ‘Remote network settings’ section, mention the remote IP address. Only the mentioned IP address will be permitted to submit an email; Others will not at all be allowed for the same.
- Open the connector properties and you will be provided with 2 options – ‘Make your new scoped connector an Externally Secured connector’ and ‘Grant the relay permission to Anonymous on new scoped connector’.
- If the submitted emails are for internal as well as external use then, use the first option. For this, you need to open CRM program properties and check the checkbox of Exchange server for enabling the permission groups. Click on OK to make changes. After this, click on the Authentication tab and mention the mechanisms, present for the incoming connections.
- When you want to connect with the receiver connector, you can go with the second option. For this, check the checkbox of ‘Anonymous users’ for assigning the users to permissions group to connectors.
Get-ReceiveConnector “CRM Application” | Add-ADPermission -User “NT AUTHORITY\ANONYMOUS LOGON” -ExtendedRights “ms-Exch-SMTP-Accept-Any-Recipient”
- For MS Exchange 2010 and Above – Follow the following steps to solve the Exchange SMTP Error 550 5.7.1 Unable To Relay fault:
- Open the Exchange Server Manager and then go to Administrative Groups
- Click on Administrative Group Name and select Server >> Server Name
- Select SMTP by selecting Protocols
- Right-click on the Default SMTP Virtual Server for selecting Properties
- Click on Access tab >> Relay >> Only List Below
- Choose the IP address on which you want to relay messages
- Enable the checkbox of “Allow all computers……..”
- Exit all the processing tabs and check whether the problem is resolved or not
In the event log of application, it is possible to check the existence of the Exchange server error along with their solutions. This will help users in analyzing the actual error cause and the time duration when Exchange SMTP Error 550 5.7.1 Unable To Relay error will occur.
It is essential to understand the cause of the error because, without this, we cannot go with the correct solution. If the error cause is corruption in the Exchange database then, this can be resolved via SysTools Exchange Recovery Software. The probability of fixing this SMTP protocol returned a permanent error 550 5.7.1 via this built-in solution is dependent on corruption intensity in EDB files.
The software repair corrupt Exchange mailbox and .edb file from corruption with no data loss. It provides an export option that allows users to export the recovered and healthy Exchange mailboxes directly to the Live Exchange Server mailboxes, Office 365 and EML, HTML, PST, PDF, MBOX, MSG file formats in a hassle freeway.
Conclusion
A high-level technical knowledge is needed to resolve Exchange SMTP Error 550 5.7.1 Unable To Relay error via the manual procedure. If the manual approaches are cleared and you are confident enough that you can fix the problem then, you can try rectifying the error on your own. So, users are suggested to contact their administrators and discuss SMTP protocol returned a permanent error 550 relay not permitted with them.
