Format error in email view (MIME Format)

Hi everyone,

I use contact form 7 on multiple site and sometimes (not always) I receive a wrong formatted email like below:

X-Mailer: PHPMailer 6.5.0 (https://github.com/PHPMailer/PHPMailer)
MIME-Version: 1.0
Content-Type: multipart/mixed;
boundary=”b1_q6iqNa8UV5e97jO8dMD5ltVaVWW0AL01qgh67utUA”
Content-Transfer-Encoding: 8bit

This is a multi-part message in MIME format.

–b1_q6iqNa8UV5e97jO8dMD5ltVaVWW0AL01qgh67utUA
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

I have tried to search this issue on internet but I can’t find any solution.
I run WordPress on Nginx & Apache (Aruba Business – Plesk) with php version: 7.4.25 FastCGI.
I have tried to add “MIME Type” text/plain .txt in “Apache & Nginx Settings” on my Plesk but nothing changed.
I use cache (WP Fastest Cache or WP Optimize) and I also use nginx cache on Plesk.

Please could someone help me to coming out?
Thanks!

• This topic was modified 3 years, 4 months ago by Jan Dembowski.

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