Invalid/Non-functioning E-mail

I receive the error message below, but the email address is valid and functions fine. (I have used 'x' to remove the email address from the public forum.)

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You have errors in your form below. Please scroll down and correct the following:

1. Invalid/Non-functioning E-mail: xxxxxxx@xxxxxxxx.com (No advertised SMTP servers are accepting mail.)

Without the email address or at least a part of the email, we can look into nothing.

The email is robbie@dwwisdom.com 

Please have Robbie add server@toastmastersclubs.org and agenda@toastmastersclubs.org.
 

Add to what?

Please have Robbie add This email address is being protected from spambots. You need JavaScript enabled to view it. and This email address is being protected from spambots. You need JavaScript enabled to view it. to his personal email whitelist/safe list and add them as contacts