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How to fix ‘550 5.1.1 : Recipient address rejected’ error in Exchange and Postfix servers

by Reeshma Mathews | Sep 22, 2016 | Server Management

In our role as Website Support specialists for web hosting companies, we’ve seen internet users sending emails to certain recipients encountering the error: 550 5.1.1 <user@domain.com>: Recipient address rejected This error is associated with recipients...

How to fix email error ‘501 5.1.7 invalid address’ in Exchange servers

by Reeshma Mathews | Sep 20, 2016 | Server Management

A commonly noted error in Microsoft Exchange 2007 server is when the emails from certain 3rd party applications or scripts fail to deliver. The mails get rejected, giving this error message in the logs: SMTP MAIL command failed Error (501) 5.1.7 Invalid address Today,...

How to fix ‘571 Delivery not authorized message refused’ error in Exchange server

by Reeshma Mathews | Sep 17, 2016 | Server Management

At times, when you send mails to a certain recipient address, it may fail to deliver, giving the following error message: An error occurred while trying to deliver this message to the recipient’s e-mail address. Diagnostic information for administrators: Remote...

How to fix Joomla ‘SMTP connect() failed’ error while sending mails

by Reeshma Mathews | Sep 16, 2016 | Server Management, Technical Support

Joomla is a commonly used content-management software for websites. In Joomla, emails are used for various purposes such as contact form submissions or password resets. Joomla ‘SMTP connect() failed’ is a commonly encountered email error in Joomla, when...

How to fix  ‘553 sorry, unknown email address’ error in Outlook, Thunderbird and Outlook Express

by Reeshma Mathews | Sep 15, 2016 | cPanel, Plesk, Server Management, Technical Support

‘553 sorry, unknown email address’ is a common email error that happens because the recipient address is invalid. The senders would see this error in the bounce message they receive. Error 553 is also called SMTP Error 5.5.3 and can happen irrespective of...
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