501 - 5.1.7 Bad sender's mailbox address syntax

published on 13/06/2011,

updated on 18/08/2021

Extract from the RFC 3463 -Enhanced Mail System Status Codes :

X.1.7 Bad sender's mailbox address syntax

The sender's address was syntactically invalid.This can apply to any field in the address.

X.1.8 Bad sender's system address

The sender's system specified in the address does not exist or
is incapable of accepting return mail.  For domain names, this
means the address portion to the right of the "@" is invalid
for mail.

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The author

Jonathan Loriaux

I've been involved in email marketing for over ten years, and my career path began on the technical side (email campaign integration) before moving on to sales (as an eCRM expert) and finally marketing consultancy. For the past 9 years, I've been the author of the Badsender.com blog. Emailing isn't just an expertise, it's truly become my passion, which is why Badsender is now my main activity, with the creation of an emailing consulting business linked to the site.

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2 responses

Matthieu

14 years ago

Hello,

Is the data still reliable from 2003?

Sincerely,
Matthieu
Jonathan Loriaux

14 years ago

Hello Matthieu,

A priori, an RFC is made to last 😉

But on the other hand, the implementation of this RFC by the various email servers will not always be up to the standard!

A+

501 - 5.1.7 Bad sender's mailbox address syntax

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