URL scheme not working !!!

Why no one helping me?
Can any punbb administrators help me?

I have  un commented it. When I consult my host they said mod_rewrite_mod is enabled.
I think that thats why wordpess htacess works fine in root folder

I am pasting entire htacess file content here

# BEGIN PunBB

# ----------------------------------------------------------------------
# Start rewrite engine
# ----------------------------------------------------------------------

<IfModule mod_rewrite.c>
    # MultiViews interfers with proper rewriting
    Options -MultiViews

    RewriteEngine On

    # Uncomment and properly set the RewriteBase if the rewrite rules are not working properly
    RewriteBase /

    RewriteCond %{REQUEST_FILENAME} !-f
    RewriteCond %{REQUEST_FILENAME} !-d
    RewriteRule . rewrite.php [L]
</IfModule>

# ----------------------------------------------------------------------
# Better website experience for IE users
# ----------------------------------------------------------------------

# Force the latest IE version, in various cases when it may fall back to IE7 mode
# github.com/rails/rails/commit/123eb25#commitcomment-118920
# Use ChromeFrame if it's installed for a better experience for the poor IE folk

<IfModule mod_setenvif.c>
    <IfModule mod_headers.c>
        BrowserMatch MSIE ie
        Header set X-UA-Compatible "IE=Edge,chrome=1" env=ie
      </IfModule>
</IfModule>

<IfModule mod_headers.c>
    # Because X-UA-Compatible isn't sent to non-IE (to save header bytes),
    # We need to inform proxies that content changes based on UA
      Header append Vary User-Agent
    # Cache control is set only if mod_headers is enabled, so that's unncessary to declare
</IfModule>

# ----------------------------------------------------------------------
# UTF-8 encoding
# ----------------------------------------------------------------------

# Use UTF-8 encoding for anything served text/plain or text/html
AddDefaultCharset utf-8

# Force UTF-8 for a number of file formats
AddCharset utf-8 .html .css .js .xml .json .rss

# ----------------------------------------------------------------------
# A little more security
# ----------------------------------------------------------------------

# Do we want to advertise the exact version number of Apache we're running?
# Probably not.
## This can only be enabled if used in httpd.conf - It will not work in .htaccess
# ServerTokens Prod

# "-Indexes" will have Apache block users from browsing folders without a default document
# Usually you should leave this activated, because you shouldn't allow everybody to surf through
# every folder on your server (which includes rather private places like CMS system folders).
<IfModule mod_autoindex.c>
    Options -Indexes
</IfModule>

# END PunBB