SES SMTP 554 Transaction failed "unbalanced quoted string"

Question

The error message provides no hint which header might be implicated nor what exactly "unbalanced" means. I've redacted the email addresses.

`{"MIME-Version":"1.0","Sender":"EDAS Conference Manager ","From":"x@domain","Date":"Sun, 13 Apr 2025 16:16:05 +0000","Reply-to":"Sabreen Fawzi Raheem ","To":"Yussif Al-Mulla , "Zainab A. Alwani"
 , Shaima Muqbel Asal ,
 Editor In Chief , Wael M El-Medany
 , Ijcds Secretary ","Message-ID":"<20250413-161605-4831@edas.info>","Subject":"[IJCDS: chairs] APC payment","Return-Path":"email","Content-Type":"multipart/mixed;
 boundary="0000000000007caf440632ab4060"","Content-Transfer-Encoding":"quoted-printable"} `

M Zubair Bin Ramzan · Answer

Try formatting the To field so that:

Every name/email pair is consistently formatted like: "Full Name"

No stray or unmatched quotes.

Avoid line breaks (
) inside the To header—these must follow header folding rules.

Example of Correct Format:

"To": ""Yussif Al-Mulla" , "Zainab A. Alwani" , "Shaima Muqbel Asal" , "Editor In Chief" , "Wael M El-Medany" , "Ijcds Secretary" "
Or without extra escaping (if you're working in code):

To: "Yussif Al-Mulla" , "Zainab A. Alwani" , "Shaima Muqbel Asal" , "Editor In Chief" , "Wael M El-Medany" , "Ijcds Secretary" 
Extra Tip:
If you're composing this message programmatically (e.g., using Python or JavaScript), use a proper email message library like:
Python: email.message.EmailMessage or email.utils.formataddr()
Node.js: nodemailer handles formatting for you.
Let me know what language you're using, and I can help you reformat your code!

regards,
M Zubair
https://zeonedge.com

SES SMTP 554 Transaction failed "unbalanced quoted string"

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