From time to time, an e-mail message may get returned to you, undelivered. If that happens, the message you receive from your domain server will most likely contain a brief explanation:
- User unknown: The message arrived at the mail server, but the server couldn't find the recipient. Check the username part of the e-mail address for errors and try sending the message again. Also, double check the domain name to ensure that you are sending it to the right organization.
- Host unknown: Your mail server could not find out the server's computer address based on the domain name. Check the domain name in the e-mail address for errors and try again.
- Message hasn't been delivered, but will try again. Your mail server failed to deliver the message, but will continue to resend it. This error message indicates a temporary communications problem that may clear up by itself. For example, this message is generated when the recipient's mail server is not functioning or is disconnected from the Internet.
- Unable to connect successfully to the destination mail server. This message usually follows the “will try again” error above. After two or more unsuccessful attempts, your mail server will no longer try resending the message.
Along with the above message (or something similar), the body of the error e-mail you will usually provide some additional information about the problem. For instance, if your e-mail was sent to multiple people, the error message will list which address it was unable to deliver the message to, so you don’t have to resend the message to everyone.
Frequently Asked Questions
Will the error message always say the same thing?
Some mail servers will utilize slightly different language, but the purpose of the message will be the same. For instance, instead of saying your mail server “will try again,” the message may say the message “has been delayed.” It means the same thing. Instead of “host unknown” or “user unknown”, you may simply get a “delivery failure” notice. In this case, double-check the entire e-mail address for errors.
What should I do if I don’t see any mistakes with the e-mail address?
It’s possible that the recipient’s mail server is experiencing technical issues or is offline. If this is the case, trying to send the message again in a few hours may solve the problem. However, don’t assume this is the case. Instead, verify the address you have. A good way to do this is to check your inbox. If you have an old message from the person you’re trying to e-mail, you can use it to ensure you have their address correct. Open that old e-mail and hit reply. This way, the address is entered for you, so there’s no chance you can miss-type it. Delete the old message and paste in the new message you were trying to send.
How many times should I try to resend a message before quitting?
If your message is being returned due to a technical issue, it could take several hours for the issue to be resolved. If the message is not critical, go ahead and retry periodically throughout the day. If it’s still not sending after 24 hours, it probably never will. If the message is urgent, don’t keep trying. Find a better way to contact the recipient, because there’s no telling how long a technical issue will take to be resolved.