404 Could not find the controller
I have also create custom resource using services module like: 

function vintervals_resource() {
  $api = array(
'registration' =&gt; array( // Resource name 
'operations' =&gt; array(
    'create' =&gt; array(
    'help' =&gt; 'Ticket System',
    'file' =&gt; array(
        'type' =&gt; 'inc',
        'module' =&gt; 'My_module_name',
        'name' =&gt; 'includes/My_module_name.services',
    ),
    'callback' =&gt; 'My_custom_callback', // callback
    'access callback' =&gt; 'user_access',
    'access arguments' =&gt; array('access content'),
    'access arguments append' =&gt; FALSE,
    'args' =&gt; array(
        array(
        'name' =&gt; 'body', // parameter name in callback
        'type' =&gt; 'string',
        'description' =&gt; 'Function to perform',
        'source' =&gt; 'data',
        'optional' =&gt; FALSE,
        'default' =&gt; '0',
        ),
    ),
    ),
    ),
)
);
return $api;
}
   // callback
 function My_custom_callback($body)
 {
      // Your work here..
      $json_array = array($body);
      $json = json_encode($json_array);
      $body_Array = json_decode($json);
      $applicationId = $body_Array[0]-&gt;appno;
      $emailid = $body_Array[0]-&gt;emailid;
      $mobileNo = $body_Array[0]-&gt;mobno;
      $password = $body_Array[0]-&gt;userpwd;
      $returnArray = array('status'=&gt;FALSE,'application_status'=&gt;-1);
      return $returnArray;
 }


URL of my web service call is : 

My domain + My endpoint + resourcename

"mydomain.com"+"api/ticketsystem"+"registration"

But it will not working directly in the browser.
For this I have sent post request to server with parameters and receive it in my callback then it's working perfectly.