SubDirectory access problem

I have installed WP on my root domain(www.domain.com)
I create a sub directory in the wp domain itself
(www.domain.com/ABP)

whenever i try to access that it gave me the 404 Error page of WP

Htaccess contents were

# BEGIN WordPress
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ – [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
</IfModule>

# END WordPress

Can some one spot me the problem???