[Solved] cURL does not connect

Hello

I had a working Joomdle site. (Joomla 2.5.9, Moodle 2.4.3+, Joomdle 0.91)
Then I had to switch my server. I backed up everything in old server and restored everything into a new one.
When I make system check with curl in new location, then I get:
Joomla cannot connect to Moodle
Moodle cannot connect to Joomla
Received empty response from Moodle

But when I make system check with file_get_contents everything is working correctly.
I need to use redirectless SSO, but then I need also the curl...

curl is installed and enabled.
I don't know what's wrong, maybe You have any ideas? I've double checked everything.

Thank You

As you say, the same setup was working on another server, so it seems clear that the problem is with the new one.

Maybe the have some restrictions on curl... I don't know.

Thank you

Your answer led me to the solution.
There was a problem with certificates in my https:// site.
When I tested "curl mysite.com " from CLI then it throws me an error:
curl: (60) SSL certificate problem, verify that the CA cert is OK. Details:
error:14090086:SSL routines:SSL3_GET_SERVER_CERTIFICATE:certificate verify failed
More details here: curl.haxx.se/docs/sslcerts.html

Then I followed instructions:

You have to put your certificate into /usr/share/ca-certificates folder instead of /usr/local/share/ca-certificates , and then append a line for your certificate into the configuration file /etc/ca-certificates.conf (e.g., “my_ca.crt“). Then you may run your "sudo update-ca-certificates --fresh" command.

Great to know that you solved it.

Thank you for the detailed follow up, I am sure it will help other users.