We recently upgraded to a Platinum subscription and as an admin I am receiving MANY info copies of emails addressed to noreply@wichitahighschoolwest1970.org with subject "Undevilered Mail Returned to Sender' from platinum.classcreator.com.

What is causing this? How do we fix?

Here is an example of the email contents:

"This is the mail system at host platinum.classcreator.com.

I'm sorry to have to inform you that your message could not be delivered to one or more recipients. It's attached below.

For further assistance, please send mail to postmaster.

If you do so, please include this problem report. You can delete your own text from the attached returned message.

The mail system

email address of calss member: mail transport unavailable"