SSL Full (Strict) Mode and Digicert Certificate

[chris33]

I have the basic CF plan. I configured my site with Full (strict) SSL Mode at first I got a free CloudFlare Cert and installed it on my server. Everything is working.

Today, I decided to install my GigiCert certificate and switch my website to use that certificate instead of the CF issued cert. When I browsed to my site, I received an error from CF stating my certificate was invalid. Full (strict) mode is supposed to work with a trusted CA cert or CF own cert but they didn’t like my Digicert certificate. How do I fix this so I can use my Digicert cert and still use Strict Mode?
SHould I turn off strict mode, replace my cert then enable strict Mode again?

[fritexvz]

Can you try switch it to Full SSL (not strict)? Deos anything changes?

Are your hostname(s) like yourdomain.com, www.yourdomain.com, subdomain.yourdomain.com included in your SSL certificate at your origin/host?

Moreover, do you have cloud at your A/CNAME records at Cloudflare DNS dashboard?

Regarding your issue about the SSL certificate invalid error:

Troubleshooting Cloudflare 5XX errors

Kindly, could you please try to follow the steps from the article below to solve your problem:

Community Tip - Fixing Error 526: Invalid SSL certificates

Error Try the suggestions in this Community Tip to help you fix Error 526: Invalid SSL certificate. Background Error 526 indicates Cloudflare is unable to successfully validate the SSL certificate on the origin web server and the SSL setting in the Cloudflare SSL/TLS app is set to Full SSL (Strict) for the website. When this happens, you’ll see “Error 526: Invalid SSL certificate”. Quick Fix Ideas If the origin server is configured to use a self-signed certificate and you’d like to have C…