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Getting "email delivery failed" email from every submission email.Asked by AnthemMusic on February 13, 2017 at 09:58 PM
Apologies for the inconveniences this may have caused to you.
If the problem persists you may also ask your email provider to white-list our IP addresses: https://www.jotform.com/help/145-Whitelisting-JotMails-IP-Addresses
Another way to resolve this would be by setting up a custom sender using the SMTP method, this way you will use your own mail server info so emails should not have problems to be delivered: https://www.jotform.com/help/244-How-to-Setup-SMTP-for-a-Form
Hope this helps.
Also, I would suggest you to check the reply-to email address in your email notifications and make sure you have selected the email address field, you should also remove these kind of emails with missing fields: