Registration module in php error when uploaded on server - php

Question

I am using registration module in which i first collect data from user and store it to a temporary database('tmp_users') and send a link via email,on clicking link via email user can activate their account(i am moving data to permanent table 'users').i have following files
studentregistration.php(A UI for registration)
processlogin.js (processing form data via jquery)
register.php (script for moving user data to 'tmp_users' and sending them link)
confirm.php(making user permanent,moving 'tmp_users' data to 'users')
in register.php i am seting two session variable $_session['email'],$_session['confirmation'] and i am generating one random unique num via
uniqid(rand()) and sending this in email as passkey which i again use in confirm.php and getting it from url by $_GET['passkey'] if passkey matched than confirming registration otherwise not.
now the problem is that this script executed successfully on my local machine but does not executed on my server.
thank in advance.......
Code for confirm.php
<?php
error_reporting(0);
require 'db/connect.php';
if(session_start())
{
$confirmation = $_GET['passkey'];
$result=$db->query("select * from tmp_users where passkey = '$confirmation'");
$count = $result->num_rows;
if($count == 1)
{
$rows = $result->fetch_all(MYSQLI_ASSOC);
/*print_r($rows);*/
foreach($rows as $row)
{
$eno = $row['eno'];
$fname = $row['fname'];
$lname = $row['lname'];
$sem = $row['sem'];
$branch = $row['branch'];
$mail = $row['mail'];
$contact = $row['contact'];
$password =$row['password'];
}
//making user permenant
$insert=$db->prepare("insert into users(eno,fname,lname,sem,branch,mail,contact,password) values(?,?,?,?,?,?,?,?)");
$insert->bind_param('ississss',$eno,$fname,$lname,$sem,$branch,$mail,$contact,$password);
$insert->execute();
$rowsaffected = $insert->affected_rows;
if($rowsaffected==1){
if($delete=$db->query("delete from tmp_users where passkey='$confirmation'"))
echo"<script>alert('Activated!!! Login Now');document.location='studentlogin.php';</script>";
else
echo "error";
}else{
echo"<script>alert('Error activating account');document.location='index.php';</script>";
}
}else{
echo"<script>alert('You are not registered');document.location='studentregistration.php';</script>";
}
}else
{
header('location:index.php');
}
?>
code for register.php
<?php
session_start();
require '../db/connect.php';
require '../phpmailer/class.phpmailer.php';
require '../mailfunction.php';
$confirmation = md5(uniqid(rand()));
$eno = $_POST['eno'];
$fname = $_POST['fname'];
$lname = $_POST['lname'];
$sem = $_POST['sem'];
$branch= $_POST['branch'];
$mail = $_POST['mail'];
$contact = $_POST['contact'];
$pw = $_POST['pw'];
$password = md5($pw);
$query = ("insert into tmp_users(passkey,eno,fname,lname,sem,branch,mail,contact,password) values (?,?,?,?,?,?,?,?,?);");
$result = $db->prepare($query);
$result->bind_param('sississss',$confirmation,$eno,$fname,$lname,$sem,$branch,$mail,$contact,$password);
if($result->execute()){
$_SESSION['mail']= $mail;
$_SESSION['confirmation'] = $confirmation;
$ToEmail = $mail;
$subject = "Activate your account";
$header = 'FROM:VGECG-LIBRARY <noreply#vgecg.ac.in>';
$MessageHTML = "Click link below to activate your account \r\n";
$MessageHTML.="<a href='localhost/projectlibrary/confirm.php?passkey=$confirmation'>Click here</a>";
$MessageTEXT='';
if(SendMail($ToEmail, $MessageHTML, $MessageTEXT))
{
print "1";
}
else {
print "";
}
}
?>