I\'m trying to make the url into
http://127.0.0.1/dev/blog/welcome but when I type that it changes the url to http://127.0.0.1/dev/blog/index.php/welcome<
For your RewriteRule, add the NC and QSA flags. The QSA ensures that query strings are appended. Unless you are planning on CodeIgniter manage your css files, images, and robots.txt, leave out the penultimate line too.
Try this:
RewriteEngine On
RewriteBase /dev/blog/
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ index.php/$1 [NC,L,QSA]
Also, check your uri_protocol in config.php. I've had some problems with WAMP not detecting it properly, and have had the most luck with setting it to PATH_INFO instead of AUTO.