htaccess not working in windows 7

[eluser]dhaulagiri[/eluser]
CI htaccess always gives 'Internal Server Error' in windows 7 WAMP server, when i want to remove 'index.php'.

Even when i did this

Code:

DirectoryIndex index.php
RewriteEngine on
RewriteCond $1 !^(index\.php|images|css|js|robots\.txt|favicon\.ico)
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ ./index.php/$1 [L,QSA]

the apache log says

Code:

perhaps misspelled or defined by a module not included in the server configuration

I am 200% sure that there is no spelling mistake
pls help

[eluser]danmontgomery[/eluser]
is mod_rewrite enabled in apache?

[eluser]dhaulagiri[/eluser]
Thank you so much, mod_rewrite was not enablled. I enabled it and it works like a charm. Thanks