MAIL FROM command failed Detail: Message submission rate for this client has exceeded the configured limit SMTP

i created a scheduler job that sends emails to assigned user’s mail and other 2 mails but sends some and fails and found
“MAIL FROM command failed Detail: Message submission rate for this client has exceeded the configured limit
SMTP code: 421 Additional SMTP info: 4.4.2
”
in log

What is your email server? :thinking:

What Is SMTP Error 421 and How to Fix It.

https://techcommunity.microsoft.com/discussions/exchange_general/4-4-2-message-submission-rate-for-this-client-has-exceeded-the-configured-limit-/4008618

Are you sure your job isn’t running too many times, or in a loop, or repeatedly for the same user…?