SMTP Error 523

Description: The total size of your mailing exceeds the recipient server’s limits

What does this mean?

The recipient’s mail server does not accept emails with the used number of mass/multiple recipients. (Eg. Using 15 email addresses in the ‘TO:’ or ‘CC:’).

How to fix SMTP Error 523?

For whichever email address failed, send the email to that user/address separately.

SMTP Error 523 Examples?

SMTP Error 450 5.2.3 Message Size greater than allowed by Remote Host

SMTP Error 552 5.2.3 Data size exceeds maximum permitted

SMTP Error 552 5.2.3 Message exceeds maximum fixed size