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WP mail sent to MS Exchange recipients = occasional email corruption?

I run into the same issue and after a research, I found out that this is a bug with class-phpmailer.php. The bug was apparently introduced in WP 4.3.2. Even if the changelog doesn’t mention it, the file was modified. Only reverting wp-includes/class-phpmailer.php to the version that was included in WP 4.3.1 fixed the issue.

The class itself also has a version, in this case I reverted to 5.2.10.

By the way, I only saw that issue also with Exchange users. But not all of them reported it.

If you are interested, some users suggest that it is an issue with fixEOL(), but I couldn’t make it work by patching it: Few chars getting replaced with ‘=’ in mail content in wp_mail()

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Categories email Tags email, html-email, phpmailer, wp-mail
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