csreid

@flow23 – I found your question when I discovered I had the same problem.

Check your Adblock settings – switching ad blockers off on the site I was having problems with has resolved this for me, and you should then be able to see the configuration section.

I don’t know why the ad blocking software (in my case AdBlock Plus) is seeing the config section as a blockable advertisement.

Now I’m seeing a string(0) “” when running that file.

That one’s still showing as blank when it’s loaded, with no visible error messages.

What I’m seeing on running that code is a blank page, with no visible result displayed.

I’ve been discussing this with our hosting partners, and they have confirmed that they are not seeing any problems on the platform or server-side based on the information we’ve provided them (the same as we’ve provided here) – and that the hosting server has a valid rDNS record matching the server’s hostname of https://www.london-drainage.co.uk (they did recommend we update this to https://www.london-drainage.co.uk as a FQDN).

What I’m currently seeing on the Diagnostic test is:

HostName: 
OS: Linux london-drainage.co.uk 4.4.0-133-generic #159-Ubuntu SMP Fri Aug 10 07:31:43 UTC 2018 x86_64

The hostname -f command through SSH is showing
london-drainage.co.uk

Not sure if it helps, but the server is using NGINX and this is the first time we’ve encountered this particular issue with Post SMTP using the same server setup.

Thank you for your assistance so far; I have raised a support ticket with our hosting partners as well to see if we can resolve this.

Yes, we do have those two lines exactly as entered in our /etc/hosts file.

HostName: 
OS: Linux london-drainage.co.uk 4.4.0-133-generic #159-Ubuntu SMP Fri Aug 10 07:31:43 UTC 2018 x86_64
PHP: Linux 7.0.13-0ubuntu0.16.04.1 en_US.UTF-8
PHP Dependencies: iconv=Yes, spl_autoload=Yes, openssl=Yes, sockets=Yes, allow_url_fopen=Yes, mcrypt=Yes, zlib_encode=Yes
WordPress: 4.9.8 en_US UTF-8
WordPress Theme: X – Child Theme
WordPress Plugins: 404page - your smart custom 404 error page, Contact Form 7 Google Analytics Integration, Contact Form 7 Modules: Hidden Fields, Contact Form 7, Cornerstone, Duplicator, Flamingo, Google Analytics for WordPress by MonsterInsights, Attercopia London Drainage Search, Page/Post Content Shortcode, Post SMTP, Redirection, Simple Custom CSS, UberMenu 3 - The Ultimate WordPress Mega Menu, UpdraftPlus - Backup/Restore, WonderPlugin Tabs, Yoast SEO, WP Fastest Cache, Smush, Contact Form 7 Redirection
WordPress wp_mail Filter(s): wp_staticize_emoji_for_email
WordPress phpmailer_init Action(s): wpcf7_phpmailer_init
Postman: 1.9.4
Postman Sender Domain (Envelope|Message): london-drainage.co.uk | london-drainage.co.uk
Postman Prevent Message Sender Override (Email|Name): No | No
Postman Active Transport: SMTP (smtp:tls:login://smtp.office365.com:587)
Postman Active Transport Status (Ready|Connected): Yes | Yes
Postman Deliveries (Success|Fail): 0 | 0

I’ve now updated the hostname to a full URI and unfortunately I am still seeing

'' does not match the expected structure for a DNS hostname, '' does not appear to be a valid URI hostname, '' does not appear to be a valid local network name

Hello again – I’m getting the hostname london-drainage at the moment, just checking the hosts file to see if there’s a reason for it showing that in preference to the full domain name.

I’m hosting with Digital Ocean; I have just done a test using a temporary Gmail account set up to use OAuth and that’s also giving the same error.