Open sandropons opened 7 years ago
👍 I am encountering this same problem, sending through Amazon SES.
This seems to be a common problem for many Wordpress plugins, as a simple google search for "wordpress duplicate mime-version" shows.
@tlovett1 is there any chance you would merge and release this in the near future?
PHPMailer in Wordpress Core clearly adds the same header (and appears to have done so for some time): https://github.com/WordPress/WordPress/blob/5eb452d15b4d99fcd19bc97dd53876547c7b2655/wp-includes/class-phpmailer.php#L2110
Also, the wp_mail
docs have an example shown passing the Content-Type
header without the MIME-Version
header: https://developer.wordpress.org/reference/functions/wp_mail/#comment-348
Since the core wp_mail
function always calls PHPMailer, this seems like a fairly straightforward change with a relatively low chance of regression. (Of course, I'm not a Wordpress plugin dev, so possibly I'm overlooking something.)
it seems that Wordpress phpmailer already inserts MIME-Version in mail headers. When "custom contact form" plugin sends the notification email, it adds the MIME-Version header and it gets duplicated. Servers may not accept the mail, resulting the error: 554 Transaction failed: Duplicate header 'MIME-Version'.