How to fix "Your site couldn't complete the loopback request" issue?

Question

PHP

Hello everyone, launched the LEMP stack. I installed Wordpress + Xenforo (XPRESS), but both in the blog engine and in the forum engine there are health errors, namely:
The loopback request to your site failed. Features that depend on its performance may not work as they should.
Error: [] cURL error 60: SSL certificate problem: unable to get local issuer certificate
And another one:
REST API request failed due to an error.
Error: [] cURL error 60: SSL certificate problem: unable to get local issuer certificate
In general, the bottom line is that I tried to fix, looked for solutions, added to php.ini [curl] curl.cainfo = /etc/ssl/ certs/ca-certificates.crt or curl.cainfo = "C:\xampp\php\extras\ssl\cacert.pem". But the problem was not solved.

Answer 1

If the site is yours, from nginx on which SSL is configured, then make sure that you have the full chain of certificates, from yours to the root, and not just the certificate of your site.
Plus, similarly try to explicitly feed the CA curl:

$ch = curl_init();
$certificate_location = ‘/usr/local/openssl-0.9.8/certs/cacert.pem’;
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, $certificate_location);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, $certificate_location);