Do you mean delete in an SQL query, or a unlink to delete files?

sory brother your are not getting me
my question is
i am working on some multiple records like here is my code
<?php
//echo $user;
session_start();
if (!isset($_SESSION['myusername']))
{
echo'<center><b>You need TO login First</b></center>';
include 'login.html';
exit();
}
else{
session_set_cookie_params(1200);
}

$user = $_SESSION['myusername'];
?>
<style>
body {
font-family:Arial, Helvetica, sans-serif;
background:#FFFFF0;
font-size:12px;
color:#000000;
}
.logout {
cursor:pointer;
background:#FFFF00;
border:#FF6600 1px solid;
width:100px;
height:30px;
font-size:14px;
font-weight:bold;
color:#FF6600;
float:right;
text-decoration:none;
font-family:Arial;
font-size:14px;
line-height:30px;
margin:50px 50px 0px 0px;
text-align:center;
}
h1 {
font-family:Arial, Helvetica, sans-serif;
font-size:20px;
color: #FF6600;
text-align:center;
margin:50px auto 0px auto;
font-weight:500;
}
.head {
font-family:Arial, Helvetica, sans-serif;
font-size:14px;
color: #000;
text-align:center;
}
.form {
font-family:Arial, Helvetica, sans-serif;
font-size:12px;
color:#666666;
line-height:18px;
background:#FBFBFB;
width:100%;
padding:20px;
border:#FFCC00 2px solid;
font-weight:bold;
}
.lable {
margin-left:100px;
}
.btn {
cursor:pointer;
background:#E0E0E0;
border:#000 1px solid;
width:100px;
height:30px;
font-size:14px;
font-weight:bold;
color:#000;
float:left;
margin-left:20px;
}
</style>
<title>View Record of Online Application</title><a href="logout.php"><span class="logout">LOGOUT</span> </a><br />
<br />
<br />
<br />
<br />
<h1>Login as&nbsp;&nbsp;<?php echo $user; ?></h1>
<?php
$host="localhost"; // Host name
$username="root"; // Mysql username
$password=""; // Mysql password
$db_name="hnit";
$tbl_name="registration";
$con = mysql_connect($host, $username, $password)or die("cannot connect");
mysql_select_db($db_name)or die("cannot select DB");
$sql="SELECT * FROM $tbl_name ORDER BY id DESC";
$result=mysql_query($sql);
$count=mysql_num_rows($result);

?>
<form name="form1" method="get" action= "">
<table width="100%" border="1" align="center" cellpadding="3" cellspacing="0" bordercolor="#FF9900" bgcolor="#FBFBFB" class="head">
<tr>
<td height="38" colspan="8" bgcolor="#FFCC00"><strong>RECORDS DISPLAYING FOR ONLINE APPLICATION </strong></td>
</tr>
<tr>
<td width="67" height="38" align="center" bgcolor="#FFFFCC"><strong>SELECT</strong></td>
<td width="48" align="center" bgcolor="#FFFFCC"><strong>Id</strong></td>
<td width="188" align="center" bgcolor="#FFFFCC"><strong>Name</strong></td>
<td width="135" align="center" bgcolor="#FFFFCC"><strong>Email ID </strong></td>
<td width="175" align="center" bgcolor="#FFFFCC"><strong>ADDRESS</strong></td>
<td width="157" align="center" bgcolor="#FFFFCC"><strong>COURSE</strong></td>
<td width="115" align="center" bgcolor="#FFFFCC"><strong>EDUCATION</strong></td>
<td width="143" align="center" bgcolor="#FFFFCC"><strong>PHONE NO </strong></td>
</tr>
<?php while($rows=mysql_fetch_array($result, MYSQL_ASSOC)){ ?>
<tr>
<td height="44" align="center" bgcolor="#FFFFFF"><input name="checkbox[]" type="checkbox" id="checkbox[]" value=" <?php echo $rows['id']; ?>"></td>
<td bgcolor="#FFFFFF"><?php echo $rows['id']; ?></td>
<td bgcolor="#FFFFFF"><?php echo $rows['name']; ?></td>
<td bgcolor="#FFFFFF"><?php echo $rows['emailid']; ?></td>
<td bgcolor="#FFFFFF"><?php echo $rows['address']; ?></td>
<td bgcolor="#FFFFFF"><?php echo $rows['course']; ?></td>
<td bgcolor="#FFFFFF"><?php echo $rows['education']; ?></td>
<td bgcolor="#FFFFFF"><?php echo $rows['phoneno']; ?></td>
</tr>
<?php } ?>
<tr>
<td height="58" colspan="8" align="center" bgcolor="#FFFFCC"><input name="delete" type="submit" id="delete" value="Delete" class="btn" style="float:none;"></td>
</tr>
<?php if($_GET['delete']){
for($i=0;$i<count($_GET['checkbox']);$i++)
{
$del_id = $checkbox[$i];
$sql = "DELETE FROM $tbl_name WHERE id='$del_id' LIMIT 1";
$result = mysql_query($sql,$con);
if (mysql_query($sql,$con))
{
echo " records is sucessfully Deleted";
}
else{
die('Error: ' . mysql_error());
}
}
if($result){
echo "<meta http-equiv=\"refresh\" content=\"0;URL=del.php\">";
}
}
mysql_close();

?>
</table>
</form>





whenever i am working on local host it work fine but after uploading file on internet
this script not deleting any records
what do i do????

If you upload the same script as it is to work on the server, it's supposed to throw errors.
Look your few variable settings, you need to change them to the server values.

Edit: Please use the code tags

Thanks for your Reply
yes brother after changing this personal information about the database still i am not able to delete the values selected by checkbox
while with the same program i am able to delete the values on my localhost
the script not work on internet why is it so
is there any change needed in php.ini
or any change needed in mysql plz tell me i am in big trouble

in my localhost my PHP Engine Type is MyISAM While on Internet My php Engine Type is InnoDB
is there any difference in both the type of PHP engine

you did the same common mistake..not doing isset on $_POST['btnName'].
your improved code here -
you can experiment with the form method=post

thanks for your reply sir but my coding is currently working on localhost but not working on internet why is it so

if your changes work then i will back to you thanks once again

you tried this code, change method in the form to 'POST' and the successive changes from $_GET to $_POST like -
if(isset($_POST['delete']) && $_POST['delete'] =='Delete')

but boss my script is not working even on local host after changing with get to post
i am remain with my $_GET Script