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SMTP Error 555

Category: Other
Tags: # # #

Description: MAIL FROM/RCPT TO parameters not recognized or not implemented.

What does this mean?

The outgoing mail server (your server) is not properly registering the email address used in either your FROM or TO settings.

How to fix SMTP Error 555?

  • Check your outgoing mail parameters to ensure proper “From:” address.
  • Check the email recipient for misspelling.