Regarding Cloudflare 520 error, may I suggest you to try looking into below articles to troubleshoot the issue:
Try the suggestions in this Community Tip to help you fix “Error 520: Web server is returning an unknown error”.
Error 520 is essentially a catch-all response when something unexpected happens or when the origin server incorrectly interprets or does not tolerate a request due to a protocol violation or an empty response. A 520 error occurs when the connection started on the origin web server, but that the request was not completed. The most common reason why this would occur …
Before moving to Cloudflare, was your Website working over HTTPS connection?
Is WP-admin set to work over SSL, also WordPress too?:
May I ask are you using some security plugin like Wordfence? If so, please read the section about
CF-Connecting-IP at the link below:
These allow you to update your Wordfence License, set your Alert Preferences, and other settings.
Est. reading time: 12 minutes
May I ask what SSL option have you got selected under the
SSL/TLS tab at Cloudflare dashboard for your domain ( Flexible, Full, Full Strict … )?
Here is a way to re-check if you correctly setup the SSL for your domain with Cloudflare:
This tutorial covers getting SSL working with Cloudflare in various different scenarios.
This assumes you already have your website set up on Cloudflare with all your DNS records set to
, if not - please visit Step 1.
Do you want the website to use HTTPS?
YesDo you already have a valid SSL certificate installed on your server (i.e. does it already load over HTTPS with a )?
If your website already works over HTTPS, you can just set your SSL mode in Cloudflare to Full (strict)…
Regarding available SSL options at Cloudflare dashboard, check here:
SSL/TLS Configuration Video:
This tutorial covers basic settings in the SSL/TLS app of the Cloudflare Dashboard, including SSL Mode [Off/Flexible/Full/Full (Strict)], Cloudflare Origin Certificates, ‘Always Use HTTPS’ and ‘Automatic HTTPS Rewrites’.
The settings covered here can all be found by visiting
Cloudflare.com, logging in, selecting the domain and choosing the SSL/TLS app.
The connection between your visitor and Cloudflare and Clou…
If any other issues appear, follow the needed steps for troubleshooting from article below:
This tutorial post covers the steps you should take if you have enabled Cloudflare, but HTTPS is not working on the site.
If your main domain is secure, but a subdomain is not, please see
SSL/TLS not working on subdomain.
1. Check that the DNS record is set to
In the DNS app in your Cloudflare dashboard, check that the DNS record for your domain is set to , not . If it is , Cloudflare is disabled on the site and none of the SSL settings will take effect.
In case you do not have an SSL certificate, you can use Cloudflare SSL, if so, kindly make sure you follow the instructions as follows on the below article to setup an SSL certificate using Cloudflare Origin CA Certificate:
Last but not least, kindly have a look here for more information regarding correct SSL settings at the SSL/TLS tab on Cloudflare dashboard:
Unencrypted & unverified connections
Imagine you open Paypal and suddenly get that warning
Would you continue? Probably not. For decades leaders in IT security have advocated that people upgrade their sites from unencrypted HTTP to secure HTTPS. And for a reason, everything you send via an HTTP connection is sent in plain text and can be intercepted at any point between you and the server.
Equally, you’d probably not proceed if you got such a warning, right?
That’s when th…
Furthermore, do not skip below step and kindly re-check if Cloudflare is allowed to connect to your origin host to as follows in the below article:
Nevertheless, Cloudflare IP addresses list can be found here: