The message could not be sent because the server rejected the sender’s email address. The sender’s email address was *** Email address is removed for privacy ***’

The message could not be sent because the server rejected the sender's email address. The sender's email address was *** Email address is removed for privacy ***'.
Subject 'test'
Server Error: 452
Server Response: 452 4.7.0 [F10] Too many messages sent.
Server: 'SMTP.iowatelecom.net'
Windows Live Mail Error ID: 0x800CCC78
Protocol: SMTP
Port: 25
Secure(SSL): No
Your server has unexpectedly terminated the connection. Possible causes for this include server problems, network problems, or a long period of inactivity.
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