Why Won't My Email Address Work (POP Client)?

Make sure you set it up exactly by looking at Email Settings.

• Make sure your user name and password are all lowercase.
   
• Make sure you have created the email accounts in your control panel. Please check these articles on how to create an email account depending on your control panel type:
  cPanel: How Do I Create Email Accounts in cPanel?
  Plesk: How To Create Email Accounts - Plesk
   
• Change the user name to the full email address. Example: [email protected] (Please replace domainname.com with your actual domain name).

Still Not Working?

• Change your incoming and outgoing mail servers from mail.example.com to the IP address listed in your Welcome email.
• Make sure you have My server requires authentication enabled in your settings; otherwise, it will not work.

Are You Able To Receive Emails, but Not Send?

If you can receive mail but aren't able to send it, this means one thing.

Your internet provider is blocking you from using anyone's outgoing mail servers but their own. Many major ISPs are blocking outgoing emails. The reason they do this is to prevent you from using their internet connection for spamming purposes. You will still be able to send emails, but only by using your ISP's outgoing mail server. Every ISP's outgoing mail address is different, but for the most part, they will be mail.yourispname.com. For example, if you had hosting with AOL.com, their outgoing mail server would look like this: mail.aol.com. If mail.yourisp.com does not work and you are still unable to send emails, you will need to call your internet service provider to find out what their outgoing mail server is.

We also have exim running on port 26 for this very reason. A possible workaround is to change your outgoing mail to port 26. 

To know more on how to deal with unsent emails, please visit this article, Are you able to receive emails but not send?

Are You Able To Send Emails, but Not Receive?

Either your domain is out of disk space, or your e-mail address itself is out. You will need to increase the amount of disk space to receive mail again. 

Please check out the article Are You Able to Send Emails but Not Receive? for more information.

Does It Say "Please Enter Your Username and Password for the Following Server," and You Are Sure You're Using the Correct Information?

Most of our servers have a 30 checks per hour limit. If you hit 30 failed login attempts while using the same IP address, you will be locked out for one hour. You will need to click Tools > Options > General > and disable where it says Check for new messages every XX minutes. If you do not want to disable it, just set it to check less often. Keep in mind that the more computers you have auto checking or checking the mail, the quicker you will hit this limit.