Access Problem

Hi everyone,
I am having security issues with mingle forum.
Right now in my .htaccess file i have denied all access to mingle forum.
<files *.php>
Deny for all
</files>

Where ever i allow these folder, i website gets hacked.

I don’t understand how i am getting this.

Thank your for your help.
!!!

http://wordpress.org/plugins/mingle-forum/