Hello @0xcffaedfe thank you for your answer, I understand where I went wrong. curl_setopt($ch, CURLOPT_HTTPHEADER, ['Authorization: KSCBasic user="dfahdushasda=", pass="afdsaedafafa=", internal="1"']); I saw that no token is issued to me, so for further requests I used the session method with cookies adding these lines curl_setopt($ch, CURLOPT_COOKIESESSION, true); curl_setopt($ch, CURLOPT_COOKIEJAR, $cookieFile); curl_setopt($ch, CURLOPT_COOKIEFILE, $cookieFile); I finally got the 200 code so I tried to make a new request, to get to know the groups ------------------------------------------------------------------------------------------------------------- $url = $ksc_server."/api/v1.0/HostGroup.FindGroups"; $ch = curl_init(); curl_setopt($ch, CURLOPT_URL,$url); curl_setopt($ch, CURLOPT_TIMEOUT, 5); curl_setopt($ch, CURLOPT_RETURNTRANSFER,1); curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false); curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false); curl_setopt($ch, CURLOPT_POST, true); curl_setopt($ch, CURLOPT_CUSTOMREQUEST, 'POST'); curl_setopt($ch, CURLOPT_COOKIESESSION, true); curl_setopt($ch, CURLOPT_COOKIEJAR, $cookieFile); curl_setopt($ch, CURLOPT_COOKIEFILE, $cookieFile); $data_string = '{"wstrFilter": "", "vecFieldsToReturn": ["id", "name"], "lMaxLifeTime": 1000}'; curl_setopt($ch, CURLOPT_HTTPHEADER, ['"Content-Type": "application/json"']); curl_setopt($ch, CURLOPT_POSTFIELDS, array()); curl_setopt($ch, CURLOPT_POSTFIELDS, $data_string); curl_setopt($ch, CURLOPT_VERBOSE, true); echo $result=curl_exec($ch); echo "<br>status Code: ". curl_getinfo($ch, CURLINFO_HTTP_CODE); if ($result === false) { die('Error fetching data: ' . curl_error($ch)); } $array=json_decode($result); print_r($array); curl_close($ch); ------------------------------------------------------------------------------- this is the result: status Code: 0 Error fetching data: Empty reply from server what am i doing wrong now?