Please help! When I send mails to two of my friends, one of them never receives it and I get a mail bounce.
That was a recent support request that we received at our Outsourced Tech Support Services, where we resolve support queries for web hosting providers.
The hosting user kept on getting the error “550 permanent failure for one or more recipients” from one of her contacts.
Why did this happen? Let’s dive into the details:
SMTP error from remote mail server after RCPT TO:<firstname.lastname@example.org>:
host mx.server.com [xxx.xxx.xxx.xxx]: 550-Verification failed for <email@example.com>
550-No Such User Here
550 Sender verify failed
Bobcares provides website management services to website owners. Email errors are the most commonly encountered issues by the end customers.
Amongst these mail errors, ‘Sender verify failed’ is a prominent error that creates so much hassle to account owners. We’ve seen that it can be caused by issues ranging from improper file permissions to RFC non-compliance. (more…)
Mail errors are commonly encountered issues in our role as Website support specialists. In Plesk Windows servers, the default mail server is MailEnable.
Plesk account owners sometimes report the MailEnable error ‘SMTP server response: 550 Requested action not taken: mailbox unavailable or not local’ when trying to send out mails or when managing their account functions through the Plesk panel. (more…)
SMTP error from remote mail server after RCPT TO:<firstname.lastname@example.org>: host domain.com [xx.xx.xx.xx]:
550-Please turn on SMTP Authentication in your mail client.
550-(mail.server.net) [xxx.xxx.xxx.xxx]:36825 is not permitted to relay through
550 this server without authentication.
All popular mail servers have SMTP authentication enabled for security protection. Mail accounts using those servers need to authenticate first, before trying to send mails.
At times, users can try to send mails from their mail clients without enabling authentication. ‘550-Please turn on SMTP Authentication’ is a commonly reported error when users try to send mails without authenticating.
At Bobcares website support services, this is a common error we see in cPanel/WHM shared hosting servers. We’ve seen that strict anti-spam rules or lack of SMTP authentication usually cause this error.
The mail user reports the error:
Task email@example.com – Sending reported error (0x800CCC78): ‘Cannot send the
message. Verify the email address in your account properties. The server
responded: 550 Access denied – Invalid HELO name (See RFC2821 18.104.22.168)
Corresponding entry in Exim logs say:
2014-09-24 07:06:31 H=isp-ip-dom.net [xxx.xxx.xxx.xxx] rejected MAIL
<firstname.lastname@example.org>: Access denied - Invalid HELO name (See RFC2821 22.214.171.124) (more…)
550: No such user here is a common error reported by cPanel users who primarily use an external mail server (like a corporate MX) to store their mail.
These include users who are trying to setup a mail forward to an external mail server, those who recently migrated or made changes to their account. (more…)
Customers who use Outlook to access email accounts hosted on cPanel/WHM email servers sometimes report the error 503 Valid RCPT command must precede DATA when trying to send their mails.
This is often reported for servers in which SMTP authentication is enabled. (more…)
Occasionally Odin Plesk customers report inability to send or receive emails reporting the following Outlook errors:
The host 'mail.domain.com' could not be found. Please verify that you have entered the server name correctly. Account: 'username', Server: 'mail.domain.com', Protocol: SMTP, Port: 25, Secure(SSL): No, Socket Error: 11001, Error Number: 0x800CCC0D.
For businesses that use SMS for business correspondence (eg., taking orders, getting instructions from customers, etc.), it is important to sync them with the official mail address. It allows easy sharing of client instructions, and facilitate faster service provisioning. (more…)
2015-03-05 11:43:41 fixed_login authenticator failed for (ispip.net) ([XX.XX.XX.XX]) [YY.YY.YY.YY]: 535 Incorrect authentication data (email@example.com)
In cPanel Exim servers, especially ones enabled with SMTP authentication, “535 Incorrect authentication data” is a common error message seen in mail logs. (more…)