Common Problems with Email Addresses

If you have an email message that won't send or get a response that an email was rejected, it could be that the address of one or more recipients was incorrect. The following are the most common problems:

The address is mistyped

Email addresses can be tricky to type. Check carefully to see if the username (the part on the left of the "@" symbol) is correct. There are some common mis-typings of domain names (the part on the right) below:

Correct   Incorrect,,,,,,,,,,,

The mail domain has been changed

Many companies and organizations change their mail domains (the part to the right of the "@" symbol). After a year or so, they stop accepting email to the old domains. The following domains have changed in the last few years and no longer accept email to the old domain.

Old Domain       ->       New Domain              (now moving to or or

kc (something)             

The address does not exist, or is suspended, or their email is full

When you get a rejection email from a mail server, there is usually a section of it that tells you why. The line will say something like:

Code 550: User account does not exist

Other codes indicate the account is suspended, or the mailbox is full, or the user is rejecting all unknown email addresses. Many mail servers now do not give a reason (to keep spammers from guessing which accounts are active) and so will just give a generic rejection notice.


Article ID: 436
Created On: Sat, Dec 18, 2010 at 11:19 PM
Last Updated On: Wed, Dec 12, 2018 at 12:38 PM
Authored by: Jon Wiederspan

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