Ajax Error – Policy restriction in effect

Hi There,

I am using Postman SMTP with mutiple sites and never had an issue, until today. When setting everything up like usual and trying to send a ‘Test Email’, I am getting the following Ajax Error. Any clue what could be causing this?

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Unexpected PHP messages corrupted the Ajax response:

Notice: mail(): Policy restriction in effect. The fifth parameter is disabled on this system in /customers/3/e/9/online-relatietherapie.nl/httpd.www/wp-content/plugins/post-smtp/Postman/Extensions/Core/Notifications/PostmanMailNotify.php on line 12
{“success”:false,”data”:{“message”:”5.7.8 Authentication failed\r\n”,”transcript”:”220 mailout1.pub.mailoutpod1-cph3.one.com ESMTP\r\nEHLO online-relatietherapie.nl\r\n250-mailout1.pub.mailoutpod1-cph3.one.com\r\n250-PIPELINING\r\n250-SIZE 104857600\r\n250-STARTTLS\r\n250-ENHANCEDSTATUSCODES\r\n250 8BITMIME\r\nSTARTTLS\r\n220 2.0.0 Ready to start TLS\r\nEHLO online-relatietherapie.nl\r\n250-mailout1.pub.mailoutpod1-cph3.one.com\r\n250-PIPELINING\r\n250-SIZE 104857600\r\n250-AUTH LOGIN PLAIN\r\n250-ENHANCEDSTATUSCODES\r\n250 8BITMIME\r\nAUTH PLAIN\r\n334 \r\nAGluZm9Ab25saW5lLXJlbGF0aWV0aGVyYXBpZS5ubABOaWV1d2VLYW5zZW4h\r\n535 5.7.8 Authentication failed\r\n”}}

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