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I'm not really sure why its not working i've tried everything here's the code i know its got nothing to do with the mysqli or mysql because i've tested it in a different area and it works
if anyone knows how to fix this then please comment below i need it sorted as fast as possible so if anyone has anything please just comment thanks!
<?php
if (!mysql_connect("localhost", "tsbannoo_client", "886215")) {
die('oops connection problem ! --> ' . mysql_error());
}
if (!mysql_select_db("tsbannoo_mybb352")) {
die('oops database selection problem ! --> ' . mysql_error());
}
$sql = "SELECT * FROM mybb0u_users WHERE username='" . $_SESSION['user'] . "'";
$res = mysql_query($sql) or die(mysql_error());
$result = mysql_query($sql);
if (!$result) {
die("Error running $sql: " . mysql_error());
}
$Row = mysql_fetch_array($res);
$ADMIN = 4;
$MOD = 6;
$VIP = 12;
$SUPERMOD = 3;
$MEMBER = 2;
$DONATOR = 11;
$AWAITINGACTIVATION = 5;
$BANNED = 7;
if ($row['usergroup'] == "4") {
} elseif ($row['usergroup'] == "6") {
} elseif ($row['usergroup'] == "12") {
} elseif ($row['usergroup'] == "3") {
} elseif ($row['usergroup'] == "2") {
session_destroy();
unset($_SESSION['user']);
echo '<META HTTP-EQUIV="Refresh" Content="0; URL=error.php?msg=(05)%20Seems%20you%20have%20not%20paid%20for%20our%20cheats%20please%20go%20to%20our%20forums%20and%20purchase%20any%20package!">';
} elseif ($row['usergroup'] == "11") {
session_destroy();
unset($_SESSION['user']);
echo '<META HTTP-EQUIV="Refresh" Content="0; URL=error.php?msg=(05)%20Seems%20you%20have%20not%20paid%20for%20our%20cheats%20please%20go%20to%20our%20forums%20and%20purchase%20any%20package!">';
} elseif ($row['usergroup'] == "5") {
session_destroy();
unset($_SESSION['user']);
echo '<META HTTP-EQUIV="Refresh" Content="0; URL=error.php?msg=(06)%20Please%20Activate%20your%20forum%20account%20and%20then%20proceed%20to%20purchasing%20a%20Package%20before%20attempting%20to%20login%20thanks!">';
} elseif ($row['usergroup'] == "7") {
session_destroy();
unset($_SESSION['user']);
echo '<META HTTP-EQUIV="Refresh" Content="0; URL=error.php?msg=(07)%20Seems%20your%20account%20is%20banned,%20HMMM%20ill%20ask%20politely%20please%20fuck%20off%20thanks!">';
}
?>

You're referring to
$_SESSION['user']
which isn't available because you didn't call session_start().