Your Web Hosting Hub email accounts can be accessed with a number of email clients, including Outlook, iPhone, Thunderbird, and many more.  Sometimes when you check your email or are first setting it up, you may receive an error message.  While error messages are different in each email client, below are some of the more common errors.

How to Troubleshoot Common Email Error Messages:

  • Incorrect Password:  This is the most common error message.  When you set up your email client, make sure that you are using the password for that email account, and not the password for the cPanel.  While the passwords can be the same, usually when the email account was setup a different password was used.  If you are not sure what the password is, you can change the password in your cPanel in the Email Accounts section.
  • Unsecure Connection (or SSL Error): All hosting accounts include a shared SSL certificate.  You can use the SSL certificate when checking mail, however you will need to use the "secure" mail server instead of  If you have the client set as SSL but are not using the secure server, it can cause a Unsecure Connection error.  For more information on how to set up an SSL connection, please see our article on connecting to email via SSL.
  • Invalid Username:  When setting up your email in a client, make sure that the username you are using is your full email address, and not your cPanel username.  The client may ask for the email address and a username, but you will need to put the full email address in both fields.
  • 550 Mailbox Quota Exceeded: This means that the recipient was not able to accept the message because their inbox was full. This is covered in our full guide 550 Mailbox Quota Exceeded
  • 550 Access denied - Invalid HELO name:Our Systems Team has begun implementing the requirement of SMTP authentication on our servers that may affect customers using an email client such as Thunderbird, Outlook or Mac Mail. If you are receiving this error message in your email client, please see our full guide 550 Access denied - Invalid HELO name.

If you are getting an error message and are still having issues connecting, please contact Tech Support and we will be happy to assist you further.

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n/a Points
2014-07-11 9:55 pm
my issue is an error message with an SMTP incorrect message that says to contact my isp.. have a link from this page to more issue.. "issue not found, click here"
17,314 Points
2014-07-12 12:37 am
Hello Camille,

Sorry to hear that you're having problems with email. Unfortunately, you have given little information with which to help you. We would need to know your domain name and any specific error message you're getting. Also, any steps to replicate the problem would help. If you're seeing a reference to your ISP, you need to speak with your internet provider - ISP stands for Internet Service Provider. We do not do this, we provide the service to host your website.

Apologies again for your problems. If you require further assistance, please give us more information and we would be happy to help.

Arnel C.

n/a Points
2014-08-01 12:52 am

I am trying to find out why I am receiving this message all of a sudden:

5.1.0 - Unknown address error 554-'5.1.0 Sender denied'

3,713 Points
2014-08-01 2:41 am
Hello Jenny,

Typically an error message of that type means that either the domain name or the actual email account you're sending from has been blocked by the recipients mail server either due to reputation or from being on a blacklist.

Please try to contact the recipient from another email account than the current one you're trying and see if you're still getting the same bounce-back error.

- Jacob

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