There are occasions in Microsoft Outlook when emails are bounced back with the "undeliverable" message attached to them. Find out what this means, and how to avoid it.
Why is My Message "Undeliverable"?
Sending an email should be a simple job. All you need to do is choose an email address to send to, give the email a subject and then type the message, remembering to click Send when you’re done.
But what does it mean when you receive a message telling you that the email is “undeliverable"? Why can the email not be sent?
There are various faults of this kind that can occur when writing email messages, from an incorrectly typed email address to a problem with your local email server or the recipient’s email server.
Depending on the type of undeliverable error message you receive, the issue can be resolved quite quickly.
Typical Email Undeliverable Messages in Microsoft Outlook
Undeliverable email errors in Microsoft Outlook will usually take the form of an email returned to you from your own local mail server or that of the recipient.
A summary of the message will be provided, along with details about the error, such as the server reporting it, as well as any information that can be passed on. Typical undeliverable email errors might be a 530 routing error, which concerns the configuration of the email server, or one that derives from the formatting of the email address.
Incorrect Email Addresses and Contacts
The first thing to check if you find any undeliverable error messages is to check the recipients of the email message for errors. Typical errors occur in the spelling of names, domains, position of the “@" symbol and any other punctuation that might be used, such as a full stop or “_".
Although these errors are the most common, if you don’t find any don’t worry. Instead check the following:
- If you are sending to multiple recipients, confirm that each is separated by a semicolon “;" (see illustration)
- If the message occurs again, check the intended recipients in your Outlook contacts list and look for any issues with these records.
Such issues might be corrupt records, where certain fields feature random characters rather than the expected text. If this happens, delete the contact entirely and then recreate it. Do not simply remove the random characters and attempt to “fix" the corrupt record as this will not work (certainly not long-term).
Email Server Problems
Another reason why you might receive an “email undeliverable" Microsoft Outlook message is when yours or the recipient’s mail server blocks the message for a reason other than problems with the email address. For instance the target email server (or the recipient’s email account) might be experiencing difficulty, or your email address or domain might be blocked. If you suspect this to be the case then you should contact your intended recipient and check with them, also confirming their email address and finding out if there is an alternative that you can use.
Alternatively the problem might be more localized. If you have investigated all other possibilities, check with your local technical support team to find out if there are any local email issues (either a connectivity issue or relating to your email account) that might be causing this problem.
Author's own experience