How can I Resolve SMTP Error 550 5.7.1 Unable to Relay in Exchange 2013

Hi Eddie,
In this error, the first digit of the code describes that if the Exchange Server accepts the command, encounters any activity or begin any suitable activity. If any syntax or connection error occurs, then they are displayed using these subsequent error codes. Like all the errors in MS Exchange, there are multiple factors which can be responsible for error 550 5.7.1 Unable to Relay in Exchange 2016, 2013, 2010:

• Multiple restrictions are imposed on the Sender’s Domain in the Recipient’s policy by the receiver domain.
• When the Outgoing mail doesn’t recognize the sender.
• If the authentication fails for the sender domain.
• Corrupted Exchange database could be another reason.

Hi Eddie,
If you are having problems with Microsoft Exchange Server and getting the error. Then, you can implement the following steps:

1. Run Exchange Server Manager.
2. Then, go to Administrative Group Name.
3. Here, select Administrative Group Name >> Server >> Server Name.
4. Click on Protocols and choose SMTP.
5. After that, right-click on Default SMTP Virtual Server to choose Properties.
6. Go to Access tab and select Relay option. Then, select Only the List Below.
7. Here, select the IP and Domain which you want to relay.
8. Enable the checkbox “Allow all the systems to successfully authenticate to relay regardless of the list above” option.
9. Now, close all the opened tabs and check if the SMTP server allows you to send emails.

The above-mentioned steps will allow you to fix Exchange 2016, 2013, 2010 error 550 5.7.1 Unable to Relay in almost all the cases but fails to work if the database is damaged or corrupted.

Hello Eddie,
As you told that your Exchange database is damaged and you are getting the SMTP error 550 5.7.1 Unable to Relay in Exchange 2013. Then, you can use a professional solution i.e. a third party application to export EDB mailbox to PST format. Using this software, you will be able to repair even the highly damaged Exchange DB files with ease.

This solution will help you to solve your issue whether you are using Exchange 2016, 2103, 2010 or other lower versions of it.