Execution in SQL does not have a problem in PHP execution error ~

Execute in SQL no problem execution error in PHP ~ ~
Error is access denied for user: [email protected] ' (Using password:no)
I used to use a blank password, there is no error, and now other files are not wrong, this one error, the code is posted as follows

 
  error_reporting (0);
Session_Start ();
Require ('.. /libs/smarty.class.php ');
$smarty = new Smarty;
$smarty->force_compile = true;
$smarty->debugging = false;
$smarty->caching = false;
$smarty->cache_lifetime = 120;



if ($_post[' OK '].value==1)
{
$username =$_post[' username '];
$userpwd =$_post[' userpwd '];
$query =mysql_query ("INSERT into User (USER,PWD)  

(' $username ', ' $userpwd ') ' Or Die (mysql_error ());
if ($query)
{
$response = "

 
  ";
}
Else
{
$response = "";

}
}
$smarty->assign ("Regstatus", $response);
$smarty->display ("reg.html");
?>

------Solution--------------------
When no one answers, you can manage the menu-"delete post."
------Solution--------------------
So, why don't you just look for reasons?

