Title: 535 Incorrect authentication data
Last modified: February 11, 2020

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# 535 Incorrect authentication data

 *  [sean1brown](https://wordpress.org/support/users/sean1brown/)
 * (@sean1brown)
 * [6 years, 4 months ago](https://wordpress.org/support/topic/535-incorrect-authentication-data-2/)
 * No longer recieving email notifacations from form entries on the site as of 13:
   50GMT on the 7th Feb last week with the status showing as 535 Incorrect authentication
   data. I have recently took over responsibility of the site so have not changed
   anything to cause this to my knowledge, any suggestions or help would be greatly
   appreciated.
 * Diagnostic Test:
 * Mailer: postsmtp
    HostName: prodisplay.com cURL Version: 7.67.0 OpenSSL Version:
   OpenSSL/1.1.1d OS: Linux prodisplay.servers.prgn.misp.co.uk 3.10.0-1062.4.1.el7.
   x86_64 #1 SMP Fri Oct 18 17:15:30 UTC 2019 x86_64 PHP: Linux 7.3.14 C PHP Dependencies:
   iconv=Yes, spl_autoload=Yes, openssl=Yes, sockets=Yes, allow_url_fopen=Yes, mcrypt
   =No, zlib_encode=Yes WordPress: 5.3.2 en_US UTF-8 WordPress Theme: Pro Display
   WordPress Plugins: Gravity Forms, Add Expires Headers Plugin, Advanced Custom
   Fields PRO, All-in-One WP Migration, Activity Log, Attachment Pages Redirect,
   Breadcrumb NavXT, Classic Editor, Contact Form 7, Cookie Notice, Custom Twitter
   Feeds, Elementor, Essential Addons for Elementor, Fast Velocity Minify, Multiple
   Columns for Gravity Forms, Gravity Forms – Placeholders add-on, Gravity Forms
   Debug Add-On, Hotjar, Leverage Browser Caching, Lightweight Grid Columns, Logo
   Slider WP, Multi Image Metabox, New RoyalSlider, PHP Compatibility Checker, Post
   Duplicator, Post SMTP, Post Types Order, Real 3D Flipbook, Really Simple SSL,
   Regenerate Thumbnails, Shortcoder, Shortcodes Ultimate, TablePress, Category 
   Order and Taxonomy Terms Order, UberMenu – Sticky Menu Extension, UberMenu 2 –
   WordPress Mega Menu Plugin, Use Google Libraries, Wordfence Security, Yoast SEO
   Premium, WP Fastest Cache, WP Gallery Custom Links, Smush WordPress wp_mail Owner:/
   home/prodisplay/public_html/wp-content/plugins/post-smtp/Postman/PostmanWpMailBinder.
   php WordPress wp_mail Filter(s): wp_staticize_emoji_for_email, PostsmtpMailer-
   >get_mail_args WordPress wp_mail_from Filter(s): wordfence::fixWPMailFromAddress
   WordPress phpmailer_init Action(s): wpcf7_phpmailer_init, PostsmtpMailer->phpmailer_smtp_init
   Postman: 2.0.10 Postman Sender Domain (Envelope|Message): prodisplay.com | prodisplay.
   com Postman Prevent Message Sender Override (Email|Name): Yes | Yes Postman Active
   Transport: SMTP (smtp:tls:plain://prodisplay.servers.prgn.misp.co.uk:587) Postman
   Active Transport Status (Ready|Connected): Yes | Yes Postman Deliveries (Success
   |Fail): 46563 | 1489

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 * 0 replies
 * 1 participant
 * Last reply from: [sean1brown](https://wordpress.org/support/users/sean1brown/)
 * Last activity: [6 years, 4 months ago](https://wordpress.org/support/topic/535-incorrect-authentication-data-2/)
 * Status: not resolved