This article provides you with information regarding common email error messages.



Every mail server is unique, and so are their error responses. It's not always easy to decipher what they're trying to tell you, so we've collected a list of the most common error messages and their variations so you can figure out what to do about it. Look for the error message that most closely matches the one you received. 



"550 Sender Verify Failed"


This usually means the inbox you're sending to or from is full, or your mail routing setting in the zone editor is wrong.

  • Full mailbox. Mailbox storage quotas are set to 250MB by default, but some plans allow you to turn off the limit and set mailbox quotas to "unlimited." If an email account is at or past its capacity, sending out from it won't work and you'll get a "Sender Verify Failed" error. To check on the mailbox quota of an email account follow this article here.
  • Mail Routing. Your domain's email routing setting may be incorrect. Check out How to Modify MX Records: Email Routing for more information.


"Authentication Failed"


An "Authentication Failed" error means the email server cannot verify that your email access is authorized. This is typically due to a mistyped password, but it can also be caused by incorrect username, connecting to the wrong server, or blacklisting. Follow these steps to resolve the issue:

  • Reset your email password.
  • If you've recently changed where your domain points, or if you've upgraded or downgraded your hosting plan, wait up to 72 hours for your new DNS settings to propagate worldwide.
  • It's also possible that your local IP is blacklisted. Wait 24 hours and try again, using webmail in the meantime. If it still doesn't work after 24 hours, check out local IP could be blacklisted.


"Certificate Name Mismatch"

This error is a warning from your email application that the certificate for SSL that the server uses doesn't match the name that your email application was expecting. 


Please see Outlook Security certificate warning


"IP Address Has Changed"


Every time you log into your webmail account, your computer's IP address is recorded. If your IP address changes while you're logged in, webmail won't recognize your new connection as valid and will automatically log you out. The easiest way to fix this error is to log in again so your new IP address is recorded. But if you're seeing this error frequently, here are a few other things you can do:

  • If possible, try using another internet connection, such as a mobile data or a WiFi, and try again.
  • If this resolves the issue, contact your internet service provider and ask to be given a static (unchanging) IP address so it won't change while you're logged in to webmail.
  • If that isn't possible, ask your ISP if the "DHCP lease time" can be increased, which will allow your login sessions to be longer.

TIP: Should you require more information regrading email error please check out our Troubleshooting Guide. Alternatively you may contact our Support Center by clicking here.