Enabling Multisite in WordPress v3.01

I am trying to enable to Multisite Network on https://cosmictechsol.com/bangor/. I have made several attempts but am unable to see the Super Admin menu in the Admin Panel.

Here are changes I made to the wp-config.php .. file

define('WP_DEBUG', false);
define('WP_ALLOW_MULTISITE', true);
define( 'SUBDOMAIN_INSTALL', false );
$base = '/bangor/';
define( 'DOMAIN_CURRENT_SITE', 'cosmictechsol.com' );
define( 'PATH_CURRENT_SITE', '/bangor/' );
define( 'SITE_ID_CURRENT_SITE', 1 );
define( 'BLOG_ID_CURRENT_SITE', 1 );

This is the .htaccess file as suggested by the system when configuring the Network

Options +FollowSymLinks
RewriteEngine On

# WordPress Rules Begin
RewriteEngine On
RewriteBase /bangor/
RewriteRule ^index\.php$ - [L]

# uploaded files
RewriteRule ^([_0-9a-zA-Z-]+/)?files/(.+) wp-includes/ms-files.php?file=$2 [L]

# add a trailing slash to /wp-admin
RewriteRule ^([_0-9a-zA-Z-]+/)?wp-admin$ $1wp-admin/ [R=301,L]

RewriteCond %{REQUEST_FILENAME} -f [OR]
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule ^ - [L]
RewriteRule  ^([_0-9a-zA-Z-]+/)?(wp-(content|admin|includes).*) $2 [L]
RewriteRule  ^([_0-9a-zA-Z-]+/)?(.*\.php)$ $2 [L]
RewriteRule . index.php [L]

# WordPress Rules End Here

I will appreciate any help to resolve this issue.
TIA