Hi Prince.gen,

try this:

$seconds = 24*60*60; // time period in seconds (24*60*60 is 1 day)
$c = JRequest::getInt('SeenIt', 0, 'cookie');
if ($c) return; /* if cookie was set, don't show anything, else... */
setcookie( 'SeenIt', 1, time()+$seconds, '/' );
return XXX; /* return module XXX, but once per time period */

replace XXX with the module id that you want to include.

Cheers,
Stephen

Thank you so much for your help.

Now I am using this code:
********************************
/* set a different "instance name" for each module that you want to show only once */
$instance_name = "shown_module_1";
if (!isset($_SESSION[$instance_name]) ||
$_SESSION[$instance_name] == false) {
$_SESSION[$instance_name] = true;
/* customise "101" to your own module number.
  * This is the one that gets shown just once per session.
  */
return xxx;
}
*******************************

Can you pls tell me what is the deference between your code and this code???

Thanks.