Member email keeps bouncing

One of our members email addresses keeps bouncing. We've never had this issue before. Member has verified email address is correct. It is not going to his spam as it just bounces. We don't know if this is security on his work email server or something on FTH. Error message received is below and the txt file is comes with is attached (i don't know how to read this to see what the issue is.

james.miller@cogentgroup.com appears to be an invalid or non-working recipient email address. (No advertised SMTP servers are accepting mail.)

*** Please check the email address to make sure it is not misspelled. ***

If you believe this warning is incorrect, please visit support.toastmastersclubs.org and post a support request message.

Maegann Yarbrough
chatstoastmasters.org
Club 8576

It should work now.