How to diasable symbols in registration

How to disable symbols in registration name account like @#$!%^&*()_+=~<.>

<?php if($mvcore['register_load'] != 'on') { echo'<div class="e_note">For the moment this page is disabled, come back later!</div>'; } ?>
<?php if($mvcore['register_load'] == 'on') { ?>
<?PHP
if (isset($_POST['r_reg_form'])){

$user_name = $_POST['r_username'];
$e_mail = $_POST['r_email'];
$user_pass = $_POST['r_password'];
$rep_pass = $_POST['r_repassword'];
$s_ques = $_POST['s_question'];
$s_answ = $_POST['s_answer'];

if($user_name == '') { $has_error = '1'; echo'<div class="e_note">Can not register, enter username!</div>'; } else {

if($mvcore['db_multi'] == '1') {
$check_user_exist = mssql_query("Select top 1 memb___id from [".$mvcore['db_name_1']."].[dbo].[MEMB_INFO] where memb___id ='".$user_name."'"); $check_user_existss = mssql_fetch_row($check_user_exist); if($check_user_existss[0] == ''){ } else { $has_error = '3'; };
$check_email_exist = mssql_query("Select top 1 mail_addr from [".$mvcore['db_name_1']."].[dbo].[MEMB_INFO] where mail_addr ='".$e_mail."'"); $check_email_existss = mssql_fetch_row($check_email_exist); if($check_email_existss[0] == ''){ } else { $has_error = '4'; };
}; if($mvcore['db_multi'] == '2') {
$check_user_exist = mssql_query("Select top 1 memb___id from [".$mvcore['db_name_1']."].[dbo].[MEMB_INFO] where memb___id ='".$user_name."'"); $check_user_existss = mssql_fetch_row($check_user_exist); if($check_user_existss[0] == ''){ } else { $has_error = '3'; };
$check_email_exist = mssql_query("Select top 1 mail_addr from [".$mvcore['db_name_1']."].[dbo].[MEMB_INFO] where mail_addr ='".$e_mail."'"); $check_email_existss = mssql_fetch_row($check_email_exist); if($check_email_existss[0] == ''){ } else { $has_error = '4'; };

$check_user_exist = mssql_query("Select top 1 memb___id from [".$mvcore['db_name_2']."].[dbo].[MEMB_INFO] where memb___id ='".$user_name."'"); $check_user_existss = mssql_fetch_row($check_user_exist); if($check_user_existss[0] == ''){ } else { $has_error = '3'; };
$check_email_exist = mssql_query("Select top 1 mail_addr from [".$mvcore['db_name_2']."].[dbo].[MEMB_INFO] where mail_addr ='".$e_mail."'"); $check_email_existss = mssql_fetch_row($check_email_exist); if($check_email_existss[0] == ''){ } else { $has_error = '4'; };
}; if($mvcore['db_multi'] == '3') {
$check_user_exist = mssql_query("Select top 1 memb___id from [".$mvcore['db_name_1']."].[dbo].[MEMB_INFO] where memb___id ='".$user_name."'"); $check_user_existss = mssql_fetch_row($check_user_exist); if($check_user_existss[0] == ''){ } else { $has_error = '3'; };
$check_email_exist = mssql_query("Select top 1 mail_addr from [".$mvcore['db_name_1']."].[dbo].[MEMB_INFO] where mail_addr ='".$e_mail."'"); $check_email_existss = mssql_fetch_row($check_email_exist); if($check_email_existss[0] == ''){ } else { $has_error = '4'; };

$check_user_exist2 = mssql_query("Select top 1 memb___id from [".$mvcore['db_name_2']."].[dbo].[MEMB_INFO] where memb___id ='".$user_name."'"); $check_user_existss2 = mssql_fetch_row($check_user_exist2); if($check_user_existss2[0] == ''){ } else { $has_error = '3'; };
$check_email_exist2 = mssql_query("Select top 1 mail_addr from [".$mvcore['db_name_2']."].[dbo].[MEMB_INFO] where mail_addr ='".$e_mail."'"); $check_email_existss2 = mssql_fetch_row($check_email_exist2); if($check_email_existss2[0] == ''){ } else { $has_error = '4'; };

$check_user_exist3 = mssql_query("Select top 1 memb___id from [".$mvcore['db_name_3']."].[dbo].[MEMB_INFO] where memb___id ='".$user_name."'"); $check_user_existss3 = mssql_fetch_row($check_user_exist3); if($check_user_existss3[0] == ''){ } else { $has_error = '3'; };
$check_email_exist3 = mssql_query("Select top 1 mail_addr from [".$mvcore['db_name_3']."].[dbo].[MEMB_INFO] where mail_addr ='".$e_mail."'"); $check_email_existss3 = mssql_fetch_row($check_email_exist3); if($check_email_existss3[0] == ''){ } else { $has_error = '4'; };

};

if(strlen($user_name) >= '11') { $has_error = '1'; echo'<div class="e_note">Account username is to large! max length: 10</div>'; };
if(strlen($user_pass) >= '11') { $has_error = '1'; echo'<div class="e_note">Account password is to large! max length: 10</div>'; };

if(strlen($user_name) <= '4') { $has_error = '1'; echo'<div class="e_note">Account username is to small! min length: 4</div>'; };
if(strlen($user_pass) <= '4') { $has_error = '1'; echo'<div class="e_note">Account password is to small! min length: 4</div>'; };

if(strlen($s_answ) >= '21') { $has_error = '1'; echo'<div class="e_note">Secret answer is to large! max length: 20</div>'; };

if($e_mail == '') { $has_error = '1'; echo'<div class="e_note">You forgot to enter email!</div>'; };
if($user_pass == '') { $has_error = '1'; echo'<div class="e_note">Account password is missing!</div>'; };
if($s_ques == '') { $has_error = '1'; echo'<div class="e_note">Select secret question from drop down!</div>'; };
if($s_answ == '') { $has_error = '1'; echo'<div class="e_note">Enter secret answer!</div>'; };
if(!filter_var($e_mail, FILTER_VALIDATE_EMAIL)) { $has_error = '1'; echo'<div class="e_note">Email is not valid.</div>'; };
if($user_pass != $rep_pass) { $has_error = '1'; echo'<div class="e_note">Can not register, repeat password did not mach!</div>'; };

if($has_error == '3') { echo'<div class="e_note">Can not register, account username already exists.</div>'; };
if($has_error == '4') { echo'<div class="e_note">Your email already in use.</div>'; };

if($has_error >= '1'){} else {

if($mvcore['db_multi'] == '1') {
$do_reg_insert = mssql_query("insert into [".$mvcore['db_name_1']."].[dbo].[MEMB_INFO] (memb___id,memb__pwd,memb_name,sno__numb,mail_addr,appl_days,modi_days,out__days,true_days,mail_chek,bloc_code,ctl1_code,admincp,SecretQuestion,SecretAnswer,acc_ip) VALUES ('".$user_name."','".$user_pass."','MVCore','111111111111111111','".$e_mail."','".date('m/d/Y')."','".date('m/d/Y')."','2015-01-01','2015-01-01','1','0','0','0','".$s_ques."','".$s_answ."','".getUserIP()."')");
$do_reg_insert = mssql_query("insert into [".$mvcore['db_name_1']."].[dbo].[AccountCharacter] (id) VALUES ('".$user_name."')");
}; if($mvcore['db_multi'] == '2') {
$do_reg_insert = mssql_query("insert into [".$mvcore['db_name_1']."].[dbo].[MEMB_INFO] (memb___id,memb__pwd,memb_name,sno__numb,mail_addr,appl_days,modi_days,out__days,true_days,mail_chek,bloc_code,ctl1_code,admincp,SecretQuestion,SecretAnswer,acc_ip) VALUES ('".$user_name."','".$user_pass."','MVCore','111111111111111111','".$e_mail."','".date('m/d/Y')."','".date('m/d/Y')."','2015-01-01','2015-01-01','1','0','0','0','".$s_ques."','".$s_answ."','".getUserIP()."')");
$do_reg_insert = mssql_query("insert into [".$mvcore['db_name_1']."].[dbo].[AccountCharacter] (id) VALUES ('".$user_name."')");

$do_reg_insert = mssql_query("insert into [".$mvcore['db_name_2']."].[dbo].[MEMB_INFO] (memb___id,memb__pwd,memb_name,sno__numb,mail_addr,appl_days,modi_days,out__days,true_days,mail_chek,bloc_code,ctl1_code,admincp,SecretQuestion,SecretAnswer,acc_ip) VALUES ('".$user_name."','".$user_pass."','MVCore','111111111111111111','".$e_mail."','".date('m/d/Y')."','".date('m/d/Y')."','2015-01-01','2015-01-01','1','0','0','0','".$s_ques."','".$s_answ."','".getUserIP()."')");
$do_reg_insert = mssql_query("insert into [".$mvcore['db_name_2']."].[dbo].[AccountCharacter] (id) VALUES ('".$user_name."')");
}; if($mvcore['db_multi'] == '3') {
$do_reg_insert = mssql_query("insert into [".$mvcore['db_name_1']."].[dbo].[MEMB_INFO] (memb___id,memb__pwd,memb_name,sno__numb,mail_addr,appl_days,modi_days,out__days,true_days,mail_chek,bloc_code,ctl1_code,admincp,SecretQuestion,SecretAnswer,acc_ip) VALUES ('".$user_name."','".$user_pass."','MVCore','111111111111111111','".$e_mail."','".date('m/d/Y')."','".date('m/d/Y')."','2015-01-01','2015-01-01','1','0','0','0','".$s_ques."','".$s_answ."','".getUserIP()."')");
$do_reg_insert = mssql_query("insert into [".$mvcore['db_name_1']."].[dbo].[AccountCharacter] (id) VALUES ('".$user_name."')");

$do_reg_insert = mssql_query("insert into [".$mvcore['db_name_2']."].[dbo].[MEMB_INFO] (memb___id,memb__pwd,memb_name,sno__numb,mail_addr,appl_days,modi_days,out__days,true_days,mail_chek,bloc_code,ctl1_code,admincp,SecretQuestion,SecretAnswer,acc_ip) VALUES ('".$user_name."','".$user_pass."','MVCore','111111111111111111','".$e_mail."','".date('m/d/Y')."','".date('m/d/Y')."','2015-01-01','2015-01-01','1','0','0','0','".$s_ques."','".$s_answ."','".getUserIP()."')");
$do_reg_insert = mssql_query("insert into [".$mvcore['db_name_2']."].[dbo].[AccountCharacter] (id) VALUES ('".$user_name."')");

$do_reg_insert = mssql_query("insert into [".$mvcore['db_name_3']."].[dbo].[MEMB_INFO] (memb___id,memb__pwd,memb_name,sno__numb,mail_addr,appl_days,modi_days,out__days,true_days,mail_chek,bloc_code,ctl1_code,admincp,SecretQuestion,SecretAnswer,acc_ip) VALUES ('".$user_name."','".$user_pass."','MVCore','111111111111111111','".$e_mail."','".date('m/d/Y')."','".date('m/d/Y')."','2015-01-01','2015-01-01','1','0','0','0','".$s_ques."','".$s_answ."','".getUserIP()."')");
$do_reg_insert = mssql_query("insert into [".$mvcore['db_name_3']."].[dbo].[AccountCharacter] (id) VALUES ('".$user_name."')");
};

echo'<div class="s_note">Register successful, account was made.</div>';

//http://s6.exedon.net/MVCore_RegisterMVCore_fabilusMVCore_3.html

if($_GET['op2'] == '' || $mvcore['friend_sys_reward'] == '0') {} else {
$Username = $_GET['op2'];
$Server = $_GET['op3'];
$GetVisitorIP = getUserIP();

if($part1[3] != '' || $GetVisitorIP != ''){
//Checking if exists

if($mvcore['db_multi'] == '1') {
$check_exist = mssql_query("Select memb___id,acc_ip from [".$mvcore['db_name_1']."].[dbo].[MEMB_INFO] where memb___id ='".$Username."'");
$exists = mssql_fetch_row($check_exist); if($exists[0] != ''){ } else { $has_error = '1'; };
$check_IP = mssql_query("Select top 9999 acc_ip from [".$mvcore['db_name_1']."].[dbo].[MEMB_INFO]"); $existsIP = mssql_fetch_row($check_IP);
if($existsIP[0] == $GetVisitorIP){ $has_error = '2'; };
}; if($mvcore['db_multi'] == '2') {
$check_exist = mssql_query("Select memb___id,acc_ip from [".$mvcore['db_name_1']."].[dbo].[MEMB_INFO] where memb___id ='".$Username."'");
$exists = mssql_fetch_row($check_exist); if($exists[0] != ''){ } else { $has_error = '1'; };
$check_IP = mssql_query("Select top 9999 acc_ip from [".$mvcore['db_name_1']."].[dbo].[MEMB_INFO]"); $existsIP = mssql_fetch_row($check_IP);
if($existsIP[0] == $GetVisitorIP){ $has_error = '2'; };
//--------------------------
$check_exist = mssql_query("Select memb___id,acc_ip from [".$mvcore['db_name_2']."].[dbo].[MEMB_INFO] where memb___id ='".$Username."'");
$exists = mssql_fetch_row($check_exist); if($exists[0] != ''){ } else { $has_error = '1'; };
$check_IP = mssql_query("Select top 9999 acc_ip from [".$mvcore['db_name_2']."].[dbo].[MEMB_INFO]"); $existsIP = mssql_fetch_row($check_IP);
if($existsIP[0] == $GetVisitorIP){ $has_error = '2'; };
}; if($mvcore['db_multi'] == '3') {
$check_exist = mssql_query("Select memb___id,acc_ip from [".$mvcore['db_name_1']."].[dbo].[MEMB_INFO] where memb___id ='".$Username."'");
$exists = mssql_fetch_row($check_exist); if($exists[0] != ''){ } else { $has_error = '1'; };
$check_IP = mssql_query("Select top 9999 acc_ip from [".$mvcore['db_name_1']."].[dbo].[MEMB_INFO]"); $existsIP = mssql_fetch_row($check_IP);
if($existsIP[0] == $GetVisitorIP){ $has_error = '2'; };
//--------------------------
$check_exist = mssql_query("Select memb___id,acc_ip from [".$mvcore['db_name_2']."].[dbo].[MEMB_INFO] where memb___id ='".$Username."'");
$exists = mssql_fetch_row($check_exist); if($exists[0] != ''){ } else { $has_error = '1'; };
$check_IP = mssql_query("Select top 9999 acc_ip from [".$mvcore['db_name_2']."].[dbo].[MEMB_INFO]"); $existsIP = mssql_fetch_row($check_IP);
if($existsIP[0] == $GetVisitorIP){ $has_error = '2'; };
//--------------------------
$check_exist = mssql_query("Select memb___id,acc_ip from [".$mvcore['db_name_3']."].[dbo].[MEMB_INFO] where memb___id ='".$Username."'");
$exists = mssql_fetch_row($check_exist); if($exists[0] != ''){ } else { $has_error = '1'; };
$check_IP = mssql_query("Select top 9999 acc_ip from [".$mvcore['db_name_3']."].[dbo].[MEMB_INFO]"); $existsIP = mssql_fetch_row($check_IP);
if($existsIP[0] == $GetVisitorIP){ $has_error = '2'; };
};

if($has_error == '1') { echo'<div class="e_note">FRIEND SYSTEM - Sorry but something is wrong with link.</div>'; };
if($has_error == '2') { echo'<div class="e_note">FRIEND SYSTEM - Seems like you are not a new user, user with your IP found.</div>'; };

if($has_error >= '1'){} else {

define("LOG_FILE", "sys/logs/Friend System.log");
error_log(date('[Y-m-d H:i e] '). "Friend System: UsedByNewAcc: $user_name | RewardGivenToAcc: $Username". PHP_EOL, 3, LOG_FILE);

//ALL OK, Can reward user.
if($Server == '1'){ //Server 1 (x10)
$RewardFriend = mssql_query("update [".$mvcore['db_name_1']."].[dbo].[".$mvcore['credits_table']."] set ".$mvcore['credits_column']." = ".$mvcore['credits_column']." + '".$mvcore['friend_sys_reward']."' where ".$mvcore['user_column']." ='".$Username."'");
echo'<div class="s_note">FRIEND SYSTEM - Your friend got '.$mvcore['money_name1'].' in server <b>x10</b> :)</div>';
} elseif($Server == '2'){ //Server 1 (x500)
$RewardFriend = mssql_query("update [".$mvcore['db_name_2']."].[dbo].[".$mvcore['credits_table']."] set ".$mvcore['credits_column']." = ".$mvcore['credits_column']." + '".$mvcore['friend_sys_reward']."' where ".$mvcore['user_column']." ='".$Username."'");
echo'<div class="s_note">FRIEND SYSTEM - Your friend got '.$mvcore['money_name1'].' in server <b>x500</b> :)</div>';
} elseif($Server == '3'){ //Server 1 (x9999)
$RewardFriend = mssql_query("update [".$mvcore['db_name_3']."].[dbo].[".$mvcore['credits_table']."] set ".$mvcore['credits_column']." = ".$mvcore['credits_column']." + '".$mvcore['friend_sys_reward']."' where ".$mvcore['user_column']." ='".$Username."'");
echo'<div class="s_note">FRIEND SYSTEM - Your friend got '.$mvcore['money_name1'].' in server <b>x9999</b> :)</div>';
};
};
} else {
echo'<div class="e_note">FRIEND SYSTEM - Sorry but something is wrong with link or your IP.</div>';
};
};
};
};
};
if($_GET['op2'] != '') {
echo '<br><h3 style="padding-left:20px;"><b>Help Your Friend!! Register HERE.</b></h3>';
} else {
if($mvcore['db_multi'] >= '2') { echo'<br><h3 style="padding-left:20px;"><b>One time register for all servers</b></h3>'; };
};
?>
<form method="POST" action="">
<input type="hidden" name="r_reg_form" >

<table align="center" width="100%">
<tr>
<td align="center">   Enter username</td>
<td align="center"><input class="input-main" type="text" name="r_username" maxlength="10"/></td>
</tr>
<tr>
<td align="center">   Enter password</td>
<td align="center"><input class="input-main" type="password" name="r_password" maxlength="10"/></td>
</tr>
<tr>
<td align="center">   Repeat Password</td>
<td align="center"><input class="input-main" type="password" name="r_repassword" maxlength="10"/></td>
</tr>
<tr>
<td align="center" title="In case we might need to contact you">   Email address</td>
<td align="center"><input class="input-main" type="text" name="r_email" maxlength="60"/></td>
</tr>
<tr>
<td align="center">   Secret question</td>
<td align="center"><select name="s_question" style="width:338px;" class="input-main">
<option value="0">-- Choose question</option>
<option value="1">What is your mother's maiden name?</option>
<option value="2">What was the name of your first school?</option>
<option value="3">Who is your favorite super hero?</option>
<option value="4">What is the name of your first pet?</option>
<option value="5">What was your favorite place to visit as a child?</option>
<option value="6">Who is your favorite cartoon character?</option>
<option value="7">What was the first video game you played?</option>
<option value="8">What was the name of your first teacher?</option>
<option value="9">What was your favorite TV show as a child?</option>
<option value="10">What city was your mother born in?</option>
</select></td>
</tr>
<tr>
<td align="center">   Secret answer</td>
<td align="center"><input class="input-main" type="text" name="s_answer" maxlength="20"/></td>
</tr>
<tr>
<td colspan="2" align="right"><button class="button-style" type="submit">Register</button></td>
</tr>
</table>
</form>
<?php } ?>