paavels

I did.

Short answer: Probably server DNS settings aren’t properly configured

Long answer:

wp-includes/http.php file has lines:

$response = array( 'headers' => array(), 'body' => '', 'response' => array('code' => false, 'message' => false), 'cookies' => array() );
		foreach ( (array) $transports as $transport ) {
			$response = $transport->request($url, $r);

Add line after to see the error:

print_r($response);