If you are trying to stablish an SSL connection using PHP cURL from windows, check that you have a file named "cacert.pem" on your PC, you can download it from the following link:

https://curl.se/docs/caextract.html

You may put it on "your php installation path"\extras\ssl ie.

Then go to the php.ini and edit the section under [curl], it originally looks something like this:

[curl]
; A default value for the CURLOPT_CAINFO option. This is required to be an
; absolute path.
;curl.cainfo =

remove the comment from ;curl.cainfo and set value corresponding to the path where the cacert.pem file is stored, like this:

[curl]
; A default value for the CURLOPT_CAINFO option. This is required to be an
; absolute path.
curl.cainfo = "<path where you stored your pem file>/cacert.pem"

Save it, if you are using a web server, restart it.

That's it.

Vires acquirit eundo!